bishopscott - bishop scott boys school

BISHOPSCOTTBOYS’SCHOOL(AffiliatedtoCBSE,NewDelhi)AffiliationNo.:330726,SchoolCampus:Chainpur,Jaganpura,By-Pass,Patna804453.PhoneNumber:7061717782,9798903550.,Web:www.bishopscottboysschool.com Email:[email protected]

ONLINESTUDYMATERIALSUBJECT-ENGLISH

SESSION-2021-22

CLASS-XII

CHAPTER:41.TheRattrap[FLAMINGO]

DAY-1

STUDYMATERIAL

Chapter4:TheRattrapBy:SelmaLagerlof

AbouttheauthorSelmaLagerlof(1858-1940)wasaSwedishwriterwhosestorieshavebeentranslatedintomanylanguages.Thisstoryissetinthemiddleof theminesofSwedenwhicharerichinironore.Thestoryisnarratedinthemannerofafairytale.Itgivesusthemessagethattheemotionsofloveandacceptancecanreform others.

TheRattrapSummaryTheRattrapisastoryaboutarattrapsellerwholeadsaverypoorlifeashisearningsareverylow.Hehastoresorttothieveryandbeggingtomakebothendsmeet.

Heisaloneinthiswholeworldandleadsamiserablelife.Sohestartsknittingupvariouskindsofthoughts.Oneofthesethoughtsisofsupposingthewholeworldasabigrattrap.Hisviewsarethattheworldoffersusvarioustypesofbaitsintheform ofcomfortsoflife.Thisinreturntrapsusintotherattrapoftheworldandleadsustovarioustypesofmiseries.

Everynight,thepeddlerhadtosearchforshelterashehasnohome.Oneeveninghewasofferedshelterbyanoldcrofter.Thenextmorninghestolethecrofter’smoneywhichhehadearnedbysellinghiscow’smilk.Tosafeguardhimself,thepeddlerchosethepaththroughtheforestwhichwassecluded,butsoonfoundhimselftrappedintheforestashewasn’tabletofindthewayoutofthedenseforest.Lateron,hefindsawayto a forge and takes shelterthere.Something unusualhappens.The ironmaster

mistakeshim asanoldfriendandinviteshim tohishouse.Thepoorpeddlerrejectstheofferduetothefearofbeingcaught.Soonheisinvitedbytheironmaster‘sdaughter.Thenextmorningheissomehow stoppedbytheironmaster’sdaughterforChristmasEveevenafterbeingcaughtthathewasapeddlerandnotCaptainStalhe.

ThenextdayafterChristmas,whentheironmasterandhisdaughtervisitthechurch,theycometoknowthatthemanisathiefwhohadstolenmoneyfrom theoldcrofter.Theironmasterandhisdaughterrepentforshelteringathiefandwonderatwhatallthingshewouldhavestolenbythattime.Herecomesatwistasinsteadofstealing,thepeddlergiftstheironmaster’sdaughterarattrap.Shefindsaletterofthanksandthestolenmoneyinsidetherattrap.ThepeddlerthanksEdlaforherkindnessandrequestshertoreturnthestolenmoneytothecrofter. Thisstorygivesusthemessagethatgoodnessinahumanbeingcanbeawakenedatanytimewithyourowngooddeeds.

DAY-2

Themeofthestory

Thethemeofthestoryisthatmost human beingsarepronetofallintothetrap of material benefit. However,every human being has an essentialgoodness that can be awakened through understanding and love.A human beinghasthetendencytoredeem himselffrom dishonestways.

Messageofthestory

The rattrap peddlerisapoorman.Herobsthesamewhogiveshim shelterandfood.ButheisreformedbythecompassionatebehaviourofayounggirlEdla.This story givesthe message thattheessentialgoodnessofmancanbeawakenedthroughloveandunderstanding.

The metaphor ofthe rattrap

The metaphor ofthe rattrapsignifies thattheworldexistsonlytotrappeoplebysettingbaitsforthem.Wheneversomeone is temptedbytheluxuries,heendsupbeingcaughtinadangeroustrap.

VIDEO-LINK

Link: https://www.youtube.com/watch?v=QFObwSI2hvw

DAY-3

PLOTOVERVIEW

Throughthestory‘TheRattrap’theauthorunderlinesthebeliefsthatessentialgoodnessinhumanbeingscanbearousedthroughsympathy,understandingandlove.Thestoryrevolvesaroundamanwhousedtosellrattraps,stealsandevenbegstomakehisendsmeet.Whilewalkinghewasstruckwithasuddenrealizationthatthewholeworldisarattrapanditoffersrichesasbaits.

Justlikearatistemptedtotouchandtakethebaitawayevenpeoplearetemptedtotouchthebaitprovidedbytheworldassoonastheygetcloserittrapsthem bringingeverythingattheend.Onedarkeveningrattrappeddlersoughtashelterinanoldcrofter’sroadsidecottage.

Theoldmanwaskind-heartedandgenerousandgavehim food,tobaccoandevenplayedacardgamewithhim.Theoldmantoldhim abouthisearningsandalsotoldhim wherehekeptthem.Thenextmorningthepeddlerstoleawaytheoldman’searningsthatwerethirtykroner.Heescapedintoabigconfusingforestandgotlost.Hegottiredandjustwhenhewasabouttoconcludethathisendisnearheheardthethumpingvoicesfrom theRamsjoironworksandhewentinsidetoseekshelterforthe night.The ownersoon came and noticed him andmistakenhim foranoldacquaintanceofhisnamedNilsOlof.

Heinvitedthepeddlertostaywithhim fortheChristmasEveasevenheandhisdaughterwereunhappyspendingtheeveallalone.ThoughthepeddlerwasreluctantwhentheownerofthemillsenthisdaughterEdlaWillmanssontopersuadehim hecouldnotsayno.Thepeddlerrealizesthatbystealingthirtykronorfrom theoldmanandacceptingtheinvitationforChristmasEvehehasknowinglythrownhimselfintothelion’sden.Whenthepeddlercametothedining tablkeallwell-groomed and dressed notasa tramp butasagentlemantheironmasterortheownerrealizersthathehadmistakenhim andhethreatenedtocallthesheriff.

Thoughhisdaughterpleadedthatthepeddlershouldnotbebotheredandhedeservesatleastonedayatpeace.Theironmasteralthough reluctantlyagreedtohisdaughter’srequestandthepeddlerwasgivenfoodandplacetosleepandwasnotdisturbedexceptforfood.Nextmorningtheironmasterandhisdaughterlearnatthechurchaboutthemanwhostolethirtykronorfromtheoldmanandescapedintothewoodsandtheyrealizeit’snoneotherthantheguestandtheyrushhomeonlytofindthatthemanwasgone.

ButhedidnotstealanythinginsteadheleftapacketforEdlaasherChristmaspresent,sheopensthepacketandfindsarattrap,threewrinkledten-kronornotesandalsoaletterwitharequesttoreturnthekronortothecrofter.

DAY-4

CHARACTERSKETCH:

PeddlerorTheRattraporCaptainVonStahle:

1.Thepeddlerwasapoorvagabond.2.Hesoldrattrapstoearnhislivingsorkeephisbodyandsoultogether.3.Healsoresortedtothieverywhenrequired.4.Hewasstruckwithadarkrealizationthattheworlditselfisarattrap

andallmenandwomenarejustlikeratsthatarevulnerabletobetrappedtovarioustypesofbaits.

5.Hewasinherentlynotabadperson.Hehadsomegoodnessinhim thatwasirkedbyEdla,theironmaster’selderdaughter.

EdlaWilmannsson:

1.Shewastheoldestdaughteroftheironmaster.2.Shewasnotatllprettybutseemedmodest,quietshy.3.Kind-hearted.4.Compassionate.5.Smartenoughtounderstandrightlyfrom thepeddler’seyesthathe

mighthaveescapedfrom jailorstolensomething.6.Shewasagreathumanbeing.

Croftor:

1.Hewaslonelyandhadnobodytotalkto.2.Hewashappytoseethepeddlerandgavehim shelter.Thisgesture

madetherpeddlerfeelwelcomedandcomfortablebecausehewasusedtoseeingsourandunwelcomedfacesordinarily.

3.Hewasgenerous.4.HehadbeenacrofteratRamsjoIronworks.5.Trustedthestrangereasilywithhisconfidaences.

Tom AnTheIronmaster(Ironworksowner):

1.Theironmasterwastheownerofthelargeironfactory,Ramsjo

Irinworks.2.Hisgreatestambitionwastoshipoutgoodironinthemarket.3.Hard-workingandconsciousofhisdutiesasheusedtogototheforge

fornightlyinspections.

DAY-5

TheRattrap-QuestionandAnswersQ1-Howdoesthepeddlerinterprettheactsofkindnessandhospitalityshownbythecrofter,theironmasterandhisdaughter?

A1-Thepeddlerwasarattrapseller.Hewasleadingalifeofmisery.Hewashomeless.Moreover,hedidn’thaveenoughmoneytosurvive.So,hehadtodependuponbeggingandthievery.Hewasonceofferedshelterbyanoldcrofter.Hewantedcompanyandshowedkindnesstowardsthepeddlerbysharinghisporridgeandtobacco.Inreturn,thepeddlerbetrayedhim andstolehismoney.

Theironmastermistookhim ashisoldcompanionCaptainVonStahle;heshowedhiskindnesstohim andinvitedhim tohishouseforChristmasEve.Thepeddlerknewthattheironmasterwasmakingamistakebythinkinghim tobehisoldfriendbutherealsohedidnotcleartheairandsimplyacceptedtheinvitation.Hedidthissothattheironmastermaygivehim somemoneyoutofpity.

EldaWilliamsonwhowastheironmaster’sdaughterinvitedhim totheirhouseinaveryfriendlyway.Also,sheinsistedherfathertolethim stayforChristmasEveevenafteritwasrevealedthathewasnotCaptainVonStahle.ThekindnatureofEldachangedthepeddlerandhenotonlythankedherbygiftingarattrapforbeingsokindandcaringbutalsorequestedhertoreturnthestolenmoneytotheoldcrofter.

Q2-Whataretheinstancesinthestorythatshowthatthecharacteroftheironmasterisdifferentfrom thatofhisdaughterinmanyways?

A2-Thecharacterofbothironmasterandhisdaughterweretotallydifferentfrom eachother.Theironmasterwasaproudman.Whenhesawthepeddler,hemistookhim asanoldregimentalcomradeandtriedtohelphim outofhissenseofpride.Whenherealizedthathehadbeenmistaken,hecalledthepeddlertobedishonestandalsowarnedhimofcallingthesheriff.Notonlythis,heworriedabouthissilverspoonswhenhecomestoknowthatpeddlerwasathief.Ontheotherhand,theironmaster’sdaughterwasakindlady,whoreallywantedtohelpthepeddler.Shetreatedhim withrespectanditwasherkindnaturewhichchangedthepeddlerandmadehim agoodperson.

Q3-Thestoryhasmanyinstancesofunexpectedreactionsfrom thecharacterstoothers’behaviour.Pickoutinstancesofthesesurprises?

A3-Thestoryhasmanyinstancesofunexpectedreactionsfrom thecharactersto

others’behavior.Forexample:Oneeveningwhenthepeddlerknockedatthedoorofalittlehut,hewasnotdisappointedbytheownerratherhewelcomedhim andtriedtobeagoodhosttohimbyofferinghim foodandplayingcardswithhim.Inanotherinstancewhenthepeddlerwentinsideaforgetoseekshelter,therehewasinvitedbytheironmastertohishouseashemistookhim asoneofhisoldregimental comrade.Butwhentheironmasterrealizedthathehadinvitedsomeunknownpersontohishouse,heaskedhim toleave.Athistime,hewasallowedtostaybyhisdaughterEldaoutofkindness.

Q4-Whatmadethepeddlerfinallychangehisways?

A4-EdlaWillimansson’skindnessreformedthepeddler.Herkindness,compassionandgenerositykilledthethiefinhim.Hegiftedherarattrap.Also,hereturnedthethreetenkronornotesthathehadstolenfrom thecrofter’shouse.Herequestedhertoreturnthemoneytotheoldcrofter.Hewrotealettertoher,thankingherfortreatinghim welljustlikeshewouldhavetreatedarealcaptain.

Q5-Howdoesthemetaphoroftherattrapservetohighlightthehumanpredicament?

A5- Theworldtemptsthehumanbeingsbyvariousgoodthingssuchastheluxuriesandjoys,foodandshelter,clothingandwarmth,etc.Theyarejustlikethebaitwhichisplantedtotrapsomeoneintherattrapoftheworld.Inthestorythepeddlerwasattractedtothethreetenkronorsofthecrofter,whichhestolefrom him.Lateron,hefoundhimselftrappedintheforestasheplannedtohidehimselfbywalkingthroughthewoods.Whenhegottrapped,hethoughtthatthiswasapunishmentforhissinof gettingluredbythemoney.

Q6-Thepeddlercomesoutasapersonwithasubtlesenseofhumour.Howdoesthisserveinlighteningtheseriousnessofthethemeofthestoryandalsoendearhim tous?

A6-Wecanseethepeddler’ssenseofhumourwhenhecomparestheworldwitharattrap.Wheneverhegetscaughtduetohisownknittedstories,hetriestoprovehisinnocencebybelievingthathehasfallenintothetrapofthisworldwhichactuallyislikearattrap.Thislightenstheseriousnessofthestoryandmakesthereadersympathizewithhim.

of 17

BISHOP SCOTT BOYS’ SCHOOL (Affiliated to CBSE, New Delhi) Affiliation No.: 330726, School Campus: Chainpur, Jaganpura,

By-Pass, Patna 804453.

Phone Number: 7061717782, 9798903550. , Web: www.bishopscottboysschool.com Email: [email protected]

STUDY COURSE MATERIAL

PHYSICS SESSION-2021-22

CLASS-Xll

TOPIC: CH-09 : RAY OPTICS

DAY-1

http://www.bishopscottboysschool.com/

mailto:[email protected]

of 17

DAY-2

of 17

DAY-3

of 17

DAY-4

of 17

DAY-5

of 11





Chemistry SESSION-2021-22

CLASS-12

TOPIC: ALDEHYDES KETONES & CARBOXYLIC ACID

TEACHING MATERIAL

Aldehydes: Aldehydes are the organic compounds in which carbonyl group is attached to

one hydrogen atom and one alkyl or aryl group.

Where R can be an alkyl or aryl group

Preparation of aldehydes:

a) By oxidation of alcohols: Oxidation of primary alcohols in presence of oxidizing agent like

K2Cr2O7/H2SO4, KMnO4,CrO3 gives aldehydes.

b) By dehydrogenation of alcohols: When the vapours of primary alcohol passed through

heated copper at 573 K, it forms aldehyde.

d) By Rosenmund reduction: Hydrogenation of acyl chloride over palladium on barium

sulphate gives aldehyde.

e) By reduction of nitriles:

i) Stephen Reaction: Reduction of nitriles in presence of stannous chloride in presence of

HCl gives imine which on hydrolysis gives corresponding aldehyde.



of 11

c) By hydration of alkynes: Ethyne on hydration with at 333 K forms

acetaldehyde.

d) From acyl chloride: Acyl chloride on treatment with dialkyl cadmium (prepared by

reaction of cadmium chloride with Grignard reagent) gives ketone.

e) From nitriles: Nitriles on treatment with Grignard reagent followed by hydrolysis give ketones.

f) By Friedel Crafts acylation reaction: Benzene or substituted benzene on treatment with acid

chloride in presence of anhydrous aluminium chloride forms ketone.

g) Preparation of aldehydes and ketones by ozonolysis of alkenes:

of 11

Reactions of aldehydes and ketones:

1. Aldehydes are generally more reactive than ketones in nucleophilic addition

reactions due to steric and electronic reasons (or inductive effect).

2. Electronic Effect: Relative reactivities of aldehydes and ketones in nucleophilic

addition reactions is due the positive charge on carbonyl carbon. Greater positive

charge means greater reactivity. Electron releasing power of two alkyl groups in

ketones is more than one in aldehyde. Therefore positive charge is reduced in

ketones as compared to aldehydes. Thus ketones are less reactive than aldehydes.

3. Stearic Effect: As the number and size of alkyl group increase, the hindrance to the

attack of nucleophile also increases and reactivity decreases. In aldehydes there is

one alkyl group and one hydrogen atom, whereas in ketones there are two alkyl

groups (same or different).

Nucleophilic addition reactions of aldehydes and ketones:

(a) Addition of hydrogen cyanide (HCN) to form cyanohydrins

(b) Addition of sodium hydrogensulphite to form bisulphate addition compound

(c) Addition of Grignard reagent (RMgX) to form alcohol

(d) Addition of alcohol:

(i) Aldehydes on addition of monohydric alcohol in presence of dry HCl forms hemiacetal and

acetal.

of 11

(ii) Ketones do not react with monohydric alcohols. Ketones react with ethylene glycol under

similar conditions to form cyclic products known as ethylene glycol ketals.

(e) Addition of ammonia and its derivatives:

Reduction of aldehydes and ketones:

(a) Reduction to alcohols:

Aldehydes and ketones on catalytic hydrogenation in presence of Ni, Pt or Pd by using lithium

aluminium hydride or sodium borohydride forms primary and secondary

alcohols respectively.

(b) Reduction to hydrocarbons:

(i) Clemmensen reduction: Carbonyl group of aldehydes and ketones is reduced to group on

treatment with zinc amalgam and concentrated hydrochloric acid.

(ii) Wolff-Kishner reduction: Carbonyl group of aldehydes and ketones is reduced to group

on treatment with hydrazine followed by heating with sodium or potassium hydroxide in high

boiling solvent such as ethylene glycol.

(iii)

Oxidation of aldehydes and ketones:

(i) Aldehydes are oxidized to acids in presence of mild oxidising agents HNO3, K2Cr2O7, KMnO4.

of 11

(ii) Ketones are oxidized under drastic conditions i.e. with powerful oxidising agents

like at higher temperature.

In case of unsymmetrical ketones cleavage occurs in such a way that keto group stays with smaller

alkyl group. This is known as Popoff’s rule.

(iii)Haloform reaction: Aldehydes and ketones having at least one methyl group linked to the

carbonyl carbon atom i.e. methyl ketones are oxidised by sodium hypohalite to sodium salts of

corresponding carboxylic acids having one carbon atom less than that of carbonyl compound. The

methyl group is converted to haloform.

Reactions of aldehydes and ketones due to -hydrogen:

(i) Aldol condensation: Aldehydes and ketones having at least one -hydrogen undergo a self

condensation in the presence of dilute alkali as catalyst to form -hydroxy aldehydes (aldol) or -

hydroxy ketones (ketol), respectively.

of 11

(ii) Cross aldol condensation: Aldol condensation between two different aldehydes and ketones is

called aldol condensation. If both of them contain -hydrogen atoms, it gives a mixture of four

products.

Canizzaro reaction: Aldehydes which do not have an -hydrogen atom undergo

self-oxidation and reduction (disproportionation) reaction on treatment with

concentrated alkali to form alcohol and salt of acid.

of 11

Test to distinguish aldehydes and ketones:

1. Tollen’s test: When an aldehyde is heated with Tollen’s reagent it forms silver mirror.

Tollen’s reagent is ammoniacal solution of

Ketones do not form silver mirror and hence do not give this test.

2. Fehling’s test: When an aldehyde is heated with Fehling’s reagent it formsreddish

brown precipitates of cuprous oxide.Fehling’s reagent: Fehling solution A (aqueous

solution of ) + Fehling solution B (alkaline solution of sodium potassium

tartarate)

Ketones do not give this test.

Carboxylic Acids:Carboxylic acids are the compounds containing the

carboxylfunctional group (-COOH).

Preparation of carboxylic acid:

(i) From alcohols: Primary alcohols are readily oxidised to carboxylic acids with common oxidising

agents such as potassium permanganate in neutral, acidic or alkaline media or by

potassium dichromate (K2Cr2O7) and chromium trioxide in acidic media.

a)

b)

(ii) From aldehydes: Oxidation of aldehydes in presence of mild oxidizing agents like Tollen’s

reagent (ammoniacal solution of ) or Fehling reagent (Fehling solution A (aqueous solution

of ) + Fehling solution B (aqueous solution of sodium potassium tartarate)) forms

carboxylic acids.

1. 2.

(iii) From alkylbenzenes: Aromatic carboxylic acids can be prepared by vigorous oxidation of alkyl

benzenes with chromic acid or acidic or alkaline potassium permanganate.

of 11

(iv) From alkenes: Suitably substituted alkenes are oxidised to carboxylic acids on oxidation with

acidic potassium permanganate or acidic potassium dichromate.

1.

2. (v) From Nitriles: Nitriles on hydrolysis in presence of dilute acids or bases forms amide which on

further hydrolysis gives carboxylic acid.

(vi) From Grignard reagent: Grignard reagents react with carbon dioxide (dry ice) to form salts of

carboxylic acids which on hydrolysis forms carboxylic acids.

(vii) From acyl halides and anhydrides: Acid chlorides when hydrolysed with water give carboxylic

acids .On basic hydrolysis carboxylate ions are formed which on further acidification forms

corresponding carboxylic acids. Anhydrides on hydrolysis forms corresponding acid(s)

(viii) From esters: Acidic hydrolysis of esters gives directly carboxylic acids while basic hydrolysis

gives carboxylates, which on acidification give corresponding carboxylic acids.

Physical properties of carboxylic acids:

(i) Solubility: As the size of alky group increases solubility of carboxylic acid decreases because

non-polar part of the acid increases

(ii) Boiling points: Carboxylic acids are higher boiling liquids than aldehydes, ketones and even

alcohols of comparable molecular masses. This is due to extensive association of carboxylic acid

molecules through intermolecular hydrogen bonding.

of 11

Acidity of carboxylic acids:

Carboxylic acids are more acidic than phenols. The strength of acid depends on extent of

ionization which in turn depends on stability of anion formed.

(i) Effect of electron donating substituents on the acidity of carboxylic acids: Electron donating

substituent decreases stability of carboxylate ion by intensifying the negative charge and hence

decreases acidity of carboxylic acids.

(ii) Effect of electron withdrawing substituent on the acidity of carboxylic acids: Electron

withdrawing group increases the stability of carboxylate ion by delocalizing negative charge and

hence, increases acidity of carboxylic acid. The effect of the following groups in increasing acidity

order is Ph< I < Br <cl< f=””>2 < CF3</cl<>

(a) Effect of number of electron withdrawing groups: As the number of electron withdrawing

groups increases –I effect increases, increasing the acid strength

(b) Effect of position of electron withdrawing group: As the distance between electron withdrawing

group and carboxylic group increases, electron withdrawing influence decreases.

Reaction of carboxylic acids:

Reactions involving cleavage of C-OH bond:

Carboxylic acids on heating with mineral acids such as or with give corresponding

anhydride.

(i) Anhydride formation:

(ii) Esterification: Carboxylic acids are esterified with alcohols in the presence of a mineral acid

such as concentrated or HCl gas as a catalyst.

(iii) Carboxylic acids react with PCl5, PCl3 and SOCl2 to form acyl chlorides.

1. 2. 3.

(iv) Reaction with ammonia (NH3): Carboxylic acids react with ammonia to give ammonium salt

which on further heating at high temperature gives amides.

i)

of 11

ii)

Reactions involving COOH group:

(i) Reduction: Carboxylic acids are reduced to alcohols in presence of LiAlH4 or B2H6.

(ii) Decarboxylation : Sodium or potassium salts of carboxylic acids on heating with soda lime

(NaOH + CaO in ratio of 3:1) gives hydrocarbons which contain one carbon less than the parent

acid.

(c) Reactions involving substitution reaction in hydrocarbon part:

(i) Hell-Volhard-Zelinsky reaction: Carboxylic acids having an -hydrogen are halogenated at the

-position on treatment with chlorine or bromine in the presence of small amount of red

phosphorus to give -halocarboxylic acids)

(ii) Ring substitution in aromatic acids: Aromatic carboxylic acids undergo electrophilic substitution

reactions. Carboxyl group in benzoic acid is electron withdrawing group and is meta directing.

i)

ii)

of 11

VIDEO-LINKS https://youtube.com/playlist?list=PLF_7kfnwLFCHUtZnRiUbHrS5WSV0BsvSg

BISHOP SCOTT BOYS’ SCHOOL (Affiliated to CBSE, New Delhi) Affiliation No.: 330726, School Campus: Chainpur, Jaganpura, By-Pass, Patna 804453. Phone Number: 7061717782, 9798903550. , Web: www.bishopscottboysschool.comEmail: [email protected]


BIOLOGY SESSION-2021-22

CLASS - 12

TOPIC: PRINCIPLES OF INHERITANCE AND VARIATION

DAY-1

TEACHINGMATERIAL

POINTS TO REMEMBER

Heredity - Heredity is a process of transmission of heritable traits from parents to their offsprings.

Genetics - Genetics is the branch of biology dealing with the principles and mechanism of inheritance and variation.

Inheritance - Inheritance is the basis of heredity and by this process, traits are passed on from the parents to the offsprings. Continuity of the gene pool is maintained by the process of inheritance.

Genes - Genes are the basic unit of inheritance and located on chromosomes.

Variation - Variation exists among individuals of one species. Variation is due to crossing over, recombination, mutation and environmental effects on the expression of genes present on chromosomes.

NCERT LINK:https://www.learncbse.in/principles-inheritance-

variation-cbse-notes-class-12-biology/

Video links: https://youtu.be/uqtpBRLvOYA

Page 1of 6

http://www.bishopscottboysschool.comemail/


http://www.learncbse.in/principles-inheritance-

DAY-2

TEACHINGMATERIAL

Mend el’s L aws of Inheritance

Gregor Johann Mendel is called “Father of genetics”.

Mendel performed experiments on Garden pea. He took 14 true-breeding plants of pea having seven distinguishable characters, which have two opposite traits.

He called genes as “factors”, which are passed from parents to

offsprings.

Genes, that code for a pair of opposite traits are called “alleles”.

He gave three laws of inheritance based on his observation:

Page 2of 6

Law of Dominance: One of the alleles is dominant and gets expressed in the phenotype in

case of the heterozygote, e.g. When we cross homozygous tall (TT) and dwarf (tt) plants, in the off springs we get all the tall plants having the genotype Tt, so tallness is a dominant trait over dwarfness.

Law of Segregation of genes:

Page 3of 6

Each allele separates during meiosis at the time of gamete formation. There is no blending and characters are passed to different gametes. Homozygotes produce only one kind of gametes and heterozygotes produce different kinds of gametes.

Law of Independent assortment: It states that alleles for different traits are inherited independently. He showed that

using a dihybrid cross.

Test Cross: It is to find out the genotype of the plant showing dominant trait, the

given plant is crossed with the recessive homozygote. The two observations are:

o If the phenotype of offsprings show only the dominant trait, then the parent plant was homozygote to the dominant trait

o If the offsprings produced are of both phenotypes, then the parent plant Page 4of 6

was heterozygote to the dominant trait.



Video links: https://youtu.be/bDygVQzCFLM

https://youtu.be/c6s_Imomolk

https://youtu.be/NQD4al7YZOM

DAY-3

Incomplete Dominance

When neither of the two alleles is dominant and the phenotype of the heterozygote does not resemble any of the parents. The heterozygote expresses intermediate or a mixture of two parents’ traits.

Example: The flower colour inheritance of snapdragon (dog flower). On

Page 5of 6


https://youtu.be/bDygVQzCFLM

https://youtu.be/c6s_Imomolk

https://youtu.be/NQD4al7YZOM

crossing true breeding red (RR) and white flower (rr), we get all pink colour flowers in the F1 generation, which on self-pollination give red: pink: white flowers in the ratio 1:2:1 in the F2 generation.

Page 6of 6

Co-dominance

When both the alleles express themselves together in an individual, they are said to be co-dominant

Example: The inheritance of the ABO blood group in humans is controlled by the gene I. The gene I has three allelic forms, IA, IB and i. In a human being, any two out of three alleles are presentIA and IB code for different kinds of sugar polymers present on the surface of RBC and ‘i’ does not produce any sugar.

IA and IB are dominant over ‘i’, but IA and IB are co-dominant and express themselves together.

Chromosomal Theory of Inheritance

Sutton and Boveri supported Mendel’s observations and stated that

chromosomes are the carrier of genes

Chromosomes occur as a homologous pair and the two alleles of a gene are Page 7of 6

located on the homologous pair of chromosomes at the same site

Homologous chromosomes separate during meiosis in the process of gamete

formation

Chromosomes segregate and assort independently

During fertilization, gametes combine and produce the offsprings with the

diploid no. of chromosomes, that is similar to the parent

Morgan extensively worked on fruit flies, Drosophila melanogaster and

provided experimental evidence to support the chromosomal theory of

inheritance.



Video links: https://youtu.be/gMxUEg25jbk

https://youtu.be/YJHGfbW55l0

https://youtu.be/M--cZ6CTRJE

DAY-4

Linkage and Recombination

Physical association of genes located on a chromosome is known as linkage.

In a dihybrid cross, if the two genes are tightly linked or present on the same chromosome than the parental combination is more prevalent than non- parental combinations or recombinants.

The linkage and recombination are directly dependent on the distance between a pair of genes. More the distance, greater is the probability of recombination.

Page 8of 6


https://youtu.be/gMxUEg25jbk

https://youtu.be/YJHGfbW55l0

https://youtu.be/M--cZ6CTRJE

Multiple alleles- When a trait is governed by more than two alleles, e.g. ABO

blood group

Polygenic Inheritance- When a trait is governed by multiple independent genes,

that have a similar or additive effect on the trait, it is known as polygenic

inheritance, e.g. eye colour, skin pigmentation, height, hair colour, etc.

Polygenic inheritance is also affected by environmental conditions.

Pleiotropy- When a single gene controls many phenotypic traits, it is known as a pleiotropic gene. The different phenotypic expressions are mostly a result of the effect of a gene on metabolic pathways.

E.g. a single gene mutation in the gene coding for the enzyme phenylalanine hydroxylase results in the disease known as phenylketonuria, which is

Page 9of 6

characterised by mental retardation, reduced hair and skin pigmentation.

Sex Determination There are different systems of sex determination present in different

organisms.

Henking first observed X chromosome and named it X body.

The chromosomes that determine the development of sexual characters are

known as sex chromosomes and the rest of the chromosomes are known as

autosomes

When the male produces two different kinds of gamete, it is known as male

heterogamety, e.g. humans, grasshoppers, drosophila, etc.

When the female produces two different kinds of gamete, it is known as female heterogamety, e.g. birds.

Sex determination in the honey bee:

Page 10of

Haplo-diploid sex-determination system.

Female (queen or worker) is formed by the fusion of an egg and sperm

and have diploid (32) no. of chromosomes

Male (drone) is formed from an unfertilized egg by parthenogenesis and have haploid (16) no. of chromosomes. Sperms are produced by

mitosis



Video links: https://youtu.be/Dzt3XdSZ1eI

https://youtu.be/eCx1TF5SZak

https://youtu.be/Ik5dfyMJkYc

Page 11of


https://youtu.be/Dzt3XdSZ1eI

https://youtu.be/eCx1TF5SZak

https://youtu.be/Ik5dfyMJkYc

Mutation

DAY-5

Any changes in the sequence of DNA is called a mutation.

Viable mutations get inherited from one generation to another. A

mutation changes the genotype as well as the phenotype of an

organism

It is linked to various diseases, but not all mutations are harmful Changes like, deletion, insertion, duplication, substitution, etc. result in

mutation.

A mutation is the major cause of cancer. There are many mutation inducing agents (mutagens) such as UV rays

There are two types of genetic mutation:

Point mutation:

There is a substitution in the single base pair of DNA, e.g. in the sickle

cell anaemia. The 6th codon of the gene coding for the �-globin chain

changes from GAG to GUG, resulting in the substitution of glutamine

by Valine.

Frameshift mutation:

It results from the insertion or deletion of one or more pairs of bases in

DNA. it changes the reading frame of triplet codons, that code for

certain amino acids of the protein.

Genetic Disorders

There are many disorders in the human being that are inherited and

caused due to mutation in the gene or alteration in chromosomes.

Pedigree Analysis helps in determining the risk of getting a genetic

disorder in the offsprings by studying the inheritance pattern of a

particular trait present in various generations of an individual.

Genetic disorders can be grouped into two types:

1. Mendelian Disorders

Page 13of

These are disorders due to alteration in the single gene.

It follows the same inheritance pattern, as per Mendel’s law.

Pedigree analysis can help trace the inheritance pattern and also

determine if the trait is dominant or recessive.

2. Chromosomal Disorders

These are disorders due to excess, absence or abnormal arrangement

of chromosomes.

Chromosomal disorders are of two types:

(i) Aneuploidy- Gain or loss of one or more chromosomes. It is due to

failure of segregation of chromatids during anaphase of meiosis.

(ii) Polyploidy- It is often found in plants. This happens due to an

increase in the full set of chromosomes. Failure of cytokinesis results in

polyploidy.

Some examples of chromosomal disorders:

Down’s syndrome- Trisomy of chromosome 21. Symptoms include mental

retardation, short stature, furrowed tongue, partially opened mouth.

Klinefelter’s syndrome- Total 47 chromosomes with one extra X

Page 14of

chromosome, i.e. XXY, They are sterile, tall, overall masculine with

feminine characteristics such as breast development (gynaecomastia).

Turner’s syndrome- Total 45 chromosomes. One X chromosome is missing,

i.e. XO. females are sterile, short stature and under-developed sexual

characters.



Video links: https://youtu.be/0q97spYaoqU

Some Questions To Practice:

Q.1. A tall plant with red flowers (dominant) is crossed with a dwarf plant

with white flowers (recessive). Work out a dihybrid cross and state the

dihybrid ratio. What will be the effect on the dihybrid ratio if the two genes

are interacting with each other?

Q.2. List out the characteristics of the chromosome theory of Inheritance.

Q.3. Why did scientists select fruit flies for his genetics experiments?

Page 15of

https://youtu.be/CrCUkYpTAm4


https://youtu.be/0q97spYaoqU

https://youtu.be/CrCUkYpTAm4

Q.4. Why does sickle-cell anaemia persist in the human population when it

is believed that the harmful alleles get eliminated from the population after

a certain time?

Page 16of

of 7



Phone Number: 7061717782, 9798903550. ,

Web: www.bishopscottboysschool.com Email: [email protected]


MATHEMATICS SESSION-2021-22

CLASS-12TH

CHAPTER : INTEGRALS

DAY-1

NCERT MATERIAL https://ncert.nic.in/textbook.php?lemh2=1-7

VIDEO LINK : https://www.youtube.com/watch?v=S-XKGBesRzk

Integration by partial fraction:



https://www.youtube.com/watch?v=S-XKGBesRzk

of 7

Example: Evaluate ∫tan 𝜃+𝑡𝑎𝑛3𝜃

1+𝑡𝑎𝑛3𝜃𝑑𝜃

of 7

Example: Resolve

𝑥3−6𝑥2+10𝑥−2

𝑥2−5𝑥+6 into partial fractions.

DAY-2

VIDEO LINK : https://youtu.be/CMG6ucGUQiU

FUNDAMENTAL THEOREM OF INTEGRAL CALCULUS

https://youtu.be/CMG6ucGUQiU

of 7

DAY-3 VIDEO LINK : https://youtu.be/C7ducZoLKgw

Evaluate the following definite integrals as limit of sums.

1. ∫ 𝑥 𝑑𝑥𝑏

𝑎

2. ∫ (𝑥 + 1)𝑑𝑥 5

0

3. ∫ (𝑥2 − 𝑥)𝑑𝑥4

1

https://youtu.be/C7ducZoLKgw

of 7

DAY-4 VIDEO LINK : https://www.youtube.com/watch?v=nopnFjMy3rQ

Some properties of definite integrals :

Evaluate :

1. ∫ log sin 𝑥 𝑑𝑥𝜋/2

0

https://www.youtube.com/watch?v=nopnFjMy3rQ

of 7

2. ∫ |𝑥3 − 𝑥|𝑑𝑥 2

−1

3. ∫ 𝑠𝑖𝑛2𝑥 𝑑𝑥 𝜋/4

–𝜋/4

DAY-5 VIDEO LINK : https://www.youtube.com/watch?v=JMqKtEC2bbY

Solve the following questions:

https://www.youtube.com/watch?v=JMqKtEC2bbY

of 6




SUBJECT COURSE MATERIALS(SCM-08)

SUBJECT-_ECONOMICS(030)______

SESSION-2021-22

CLASS-_XII

Human Capital Formation

DAY-01

Human Capital

Human Capital It refers to the stock of ‘skill and expertise’ of a nation at a point of time. It is the

sum total of skill and expertise.

Human Capital Formation It is the process of adding to the stock of human capital over time.

Physical Capital It refers to the stock of produced means of production. It consists of machines,

production plants etc.

Financial Capital It refers to the stocks/shares of the companies or these are simple financial claims

against assets of the companies.

Major Sources of Human Capital in Country

1. Expenditure on Education: It is one of the primary sources of human capital development.

Investment in education is not only highly productive, but it also generates growing returns

and promotes economic progress. Of all the resources, education receives the greatest

attention because it contributes the most to the country's development.

2. Expenditure on Health: Health is a crucial factor for the development of a nation. An ailing

individual with insufficient health and medicare facilities is forced to stop working, resulting

in a loss of output, also in case the said individual works despite poor health, then also there

is a loss of productivity and output. The various forms of health expenditure are preventive

medicine, curative medicine, social medicine, provision of clean drinking water,

3. On the job training: On and off campus training of employees, in terms of training by a

supervisor in the firm itself, or training at an off campus location enhances the skill and

productivity of an individual, and makes him more accustomed to the work environment and

work he is supposed to do.



of 6

4. Migration: Migration to other locations within or outside the country either due to

unemployment or better professional opportunities is also a source of human capital formation.

5. Information: A person incurs expenses in terms of acquiring information about labour

markets, product markets, capital markets, and education, health in order to ensure efficient

utilisation of human stock and take better decisions regarding them. This is also a part of human

capital formation.

DAY-2

Importance of Human Capital Formation

1. Boosts productivity: Human capital development through investment in education boosts

productivity and output by ensuring that workers are aware and skilled (use of the resources).

Increased productivity and quality output are dependent on people's technical skills, which

can only be acquired through the investment in education or training, as well as their overall

health.

2. Control of population growth: It has been noticed that educated people have smaller

families than illiterate people, implying that education must be widely diffused to reduce

population growth.

3. Improves Quality of life: The quality of a population is determined by a person's degree of

education, health, and skill development. Human capital development not only makes people

more productive and creative, but it also changes their lives.

4. Increases life expectancy: Human capital development increases people's life expectancy.

People can live a healthy and long life if they have access to health care and nutritious food.

As a result, the quality of life improves.

5. Effective use of physical capital: A person who is well trained, with appropriate skills will

have a better understanding of the physical tools and equipment, as well as he will be able to

find out the best possible ways to make the best use of them.

Reasons for Poor Human Capital Formation

1. Insufficient Resources: The resources given to the development of human capital have been

far less than those required to meet the country's educational and health demands. As a result,

the facilities for developing human capital have remained woefully inadequate.

2. Serious Inefficiencies: There are numerous wastes of society's resources because the

capabilities of educated individuals are either not exploited or are underutilized while they

are unemployed. Other inefficiencies that have not been promptly and appropriately

addressed include widespread literacy, the non-education of children, especially in rural areas

and slums, and poor health facilities.

3. High Growth of population: The quality of human capital has deteriorated as the population

continues to grow.

of 6

4. Lack of proper manpower planning: There is a mismatch between demand and supply for

numerous categories of human resources, particularly in the case of highly qualified

employees. Waste of human resources has come from the lack of such balancing.

5. High Poverty Levels: Majority of the population lives in poverty, and they don’t even have

access to the three basic necessities of life, this ultimately impacts the building of human

capital.

DAY-03

Physical Capital

It encompasses all the inputs required for further production, such as plant and machinery, factories,

buildings, raw materials, and so on.

Difference Between Human Capital and Physical Capital

Basis Human Capital Physical Capital

Tradability

Human capital is an intangible asset that

cannot be purchased on the open

market.

Physical capital is observable and can be

easily traded.

Depreciation

Human capital depreciation can be

reduced by continuing to invest in

education, health, and education.

With the passage of time, it depreciates.

Mobility Human capital is less mobile between

countries. It is more movable across borders.

Seperation Human capital (such as a person's skills)

cannot be divorced from one's own.

Separation of physical capital (such as

machinery) from its owners.

Origination

Human capital formation is partly a

social process and partly a voluntary

decision of the human capital possessor.

Physical capital is the result of the

owner's deliberate decision and is

primarily an economic and technological

process.

Creation

Human capital building should be

accomplished by deliberate policy

formulation.

It is simple to form with machines.

Difference between Human Capital and Human Development

Basis Human Capital Human Development

of 6

Viewpoint

Human capital views education

and health as ways to boost labour

productivity.

Human development is based on the belief

that education and health are essential

components of human well-being.

Investment in

education and

health

Investment in education and

health is considered unproductive

in human capital if it does not

boost output of commodities and

services.

Investment in education and health are

considered productive in the case of human

development, even if they do not result in

increased output.

Focus

Human capital views people to an

end, with the goal of increasing

production.

From the standpoint of human development,

human welfare should be enhanced by

investments in education and health, as

every individual has the right to be literate

and live a healthy life.

DAY-04

Education

It refers to the process of teaching, training, and learning, which takes place mostly in schools and

colleges, to increase their knowledge and skills.

Growth of Education Sector in India

In the sphere of education, there has been significant progress. From 1950 to 1951, the number of

schools climbed from 230.7 thousand to 1,215.8 thousand (2005-06). During the same time, the

number of teachers climbed from 751 thousand to 6010 thousand, while the number of pupils

increased from 23,800 thousand to 2,22,700 thousand.

Gross Enrollment Ratio

The Gross Enrollment Ratio (GER) is the total number of students enrolled in a grade, cycle, or

level of education, regardless of age, represented as a percentage of the population of the matching

eligible official age group in a particular school year. From 82 percent in 1950-51 to 94.85 percent

in 2005-06, GER in primary education has gradually increased.

Education Sector in India

Elementary Education: Elementary education in India entails eight years of learning

beginning at the age of six, i.e., primary, and middle school education combined. As a result,

elementary education is the bedrock upon which the development of all citizens and the

nation is built. Elementary education has been made compulsory and free by the government.

However, achieving the goal of universal primary education in India has proven to be a

difficult task.

Secondary Education: Secondary education, which begins in grades IX and X and ends in

grades XI and XII, strives to develop basic skills and analytical ability. It serves as a

stepping- stone to more advanced professional and technical training.

of 6

Higher Education: Both general and technical education are part of the higher education

system. Since independence, higher education has grown in leaps and bounds. The country's

university population has grown from 27 in 1950-51 to 350 in 2005-06.

The University Funding Commission (UGC) is responsible for promoting and coordinating

university education, as well as determining and maintaining standards in teaching, assessment, and

research, as well as allocating and disbursing grants to universities.

Problems/ Weakness in Education Sector

1. High Illiteracy: According to the 2001 census, the literacy rate was 64.8 percent, which is

still considerably below the national average of 100 percent.

2. Gender Bias: In India, education is skewed toward women. The number of girls enrolled in

basic and upper primary levels is significantly lower than that of boys.

3. Low Quality Education: The educational system is of poor quality, with major focus on

theory and learning, and less consideration to practical learning. Though the new education

policy has a number of positive aspects that may contribute to the betterment of the education

sector in India.

4. Lack of Vocational and Technical Training: There is an overabundance of emphasis on

general education, which neglects vocational and technical education.

5. Low Level of Government Expenditure: The actual amount of spending is far less than the

desired level of expenditure which should be made.

DAY-05

Future Prospects India government considers education a key sector where considerable growth and.development is required.

Thus, it has set some future prospects for framing its policies.

These prospects are discussed below

Education for All : Still a Distant Dream

Although the education level in India has risen for both adults as well as for youth. Still the number of

illiterates in India are as much as the population was at the time of Independence.

In 1950, when the Constitution of India was passed by the constituent assembly, it was noted in the directive

principles of the constitution that the government should provide free and compulsory education for all

children up to the age of 14 years within 10 years from the commencement of the constitution.

The following factors makes education still a distant dream

Large number of illiterates

Inadequate vocationalisation

Gender bias

Low rural access level

Privatisation

Low government expenditure on education

Gender Equity : Better than Before

The differences in literacy rates between males and females are narrowing, signifying a positive

development in gender equity; still the need to promote education for women in India is imminent for

various reasons, such as

of 6

Improving economic independence.

Social status of women.

Healthcare of women and children.

Therefore, we cannot show the satisfaction about the upward movement in literacy rates as we have miles to

go in achieving cent percent adult literacy.

In India, Mizoram, Kerala, Goa and Delhi are the states having high literacy rate, while Bihar, Uttar

Pradesh, Rajasthan and Arunachal Pradesh are the educationally backward states. The educational

backwardness is due to social and economic poverty of the people.

Higher Education : A Few Takers

The Indian education pyramid is steep, indicating lesser and lesser number of people reaching the higher

education level.

As per NSSG (National Sample Survey Organisation) data, in the year 2007-08, the rate of unemployment

for youth with education up to secondary level and above was 18.1% whereas, the rate of unemployment for

youth with education up to primary level was only 11.6%.

Therefore, the government should increase allocation for higher education and also improve the standard of

higher education institutes, so that students are imparted employable skills in such institutions



Phone Number: 7061717782, 9798903550. ,

Web: www.bishopscottboysschool.com Email: [email protected]


PHYSICAL EDUCATION SESSION-2021-22

CLASS-12

TEST AND MEASUREMENT IN SPORTS

Computation of Fat Percentage The fat percentage or the amount of fat a person carries and whether he/she is normal, underweight or overweight can be calculated through computation of fat percentage. This can be done by BMI Body Mass Index (BMI) is a measure of body fat calculated on the basis of height and weight. To calculate BMI, take the weight in kilograms and divide it by square of height taken in metres.

𝐵𝑀𝐼 =𝐵𝑜𝑑𝑦 𝑤𝑒𝑖𝑔ℎ𝑡 𝑖𝑛 𝑘𝑔

(𝐻𝑒𝑖𝑔ℎ𝑡 𝑖𝑛 𝑚𝑒𝑡𝑒𝑟𝑠)2

With the help of BMI, it is determined whether a person in normal, underweight overweight.

BMI WEIGHT STATUS

Below 18.5 Underweight

18.5-24.9 Normal

25.0-29.9 Overweight

30.0 and above Obese

Slaughter-Lohman Children Skinfold This is a standard skinfold test for measuring body fat in children under the age group of 6-17 years. The digital skinfold calliper is used to measure the triceps and calf region and then the measurement is inserted into a formula.

Slaughter-Lohman Children Skinfold Formula For Triceps, measure vertically on back of arm midway between top of shoulder point and elbow. For Calf, measure the inside of the right lower leg at the place where there is greatest calf girth.

Formula for males (6 to 17 years):

% body fat = (0.735 x sum of skinfold + 1.0)

Formula for females (6 to 17 years):



% body fat = (0.610 x sum of skinfold + 5.1)

Sum of skinfolds = Triceps + Calf

Measurement of Muscular Strength Muscular strength refers to the amount of force the muscle or group of muscles can exert against resistance for short duration like in anaerobic activities. Muscular strength can be measured by Kraus Weber Test.

Kraus Weber Test Kraus Weber Test originated in a posture clinic and was developed as a diagnosis and treatment of low back pain. Soon, it became familiar as Kraus Weber test of minimum muscular fitness. The test consists of six items which indicate the level of muscular strength and flexibility of key muscle groups.

Note - The tests are done without the subject wearing shoes. The six test items of the Kraus Weber muscular strength test are given below

1. Abdominals Plus Psoas (hip flexing) Muscles

2. Abdominals Minus Psoas

3. Psoas or P

4. Upper Back or UB

5. Lower Back or LB

6. Back and Hamstring or BH

Motor Fitness Test-AAHPER The AAHPER (American Alliance for Health, Physical Education and Recreation) youth fitness test was formed in 1965 in the United States, but this was revised in 1976. Now dance (AAHPERD) is also added. This test was administered on school students of 17 years age. The students are advised to warm up before they participate in the test. All the students must be medically fit. This test has the following six items:

1. (a) Pull-Ups (For Boys)

Purpose To measure arm and shoulder strength.

Procedure The bar is adjusted according to the height of the boy. The bar is held with palms facing away. He is then asked to raise his body so that the chin reaches the level of the bar. One score is awarded for each pull-up. One trial is given before the start of the test.

(b) Flexed Arm Flang (For Girls)

Purpose To measure arm and shoulder strength.

Procedure The bar is adjusted according to the standing height of the girl. The bar is held with over hand grasp. The girl lifts her body up with the assistance of testing personnel so that her chin reaches the bar level. The time in seconds she holds the bar is taken as her score.

2. Flexed Leg Sit-ups

Purpose To measure abdominal strength and endurance.

Procedure The youth is asked to lie on the floor on his/ her back keeping knees bent. The angle of knees should be around 90°. The feet are held by a partner,’ the youth’ puts hands behind the head with fingers interlocked. Then the youth curls up and touches the elbows to knees. The score is counted as maximum number of sit-ups in 60 sec.

3. Shuttle Run

Purpose To measure speed and agility.

Procedure Two parallel lines are marked 30 feet apart and two wooden-blocks 2 x 2 x 4 inches are kept on one side of a marked line. The youth stands behind the line opposite to the line where wooden blocks are placed. At the start signal, the youth runs towards the wooden blocks and picks up one of them, carrying it back to the line from where the test started. Then places it behind the line, runs back, picks up the second block and carries back-to the starting line. Two trials are allowed and best score of the two is noted down.

4. Standing Long Jump

Purpose To measure power.

Procedure The youth is asked to stand behind the restraining line with feet apart and he/she bends the knees and swings arms before jumping. The youth lands on both feet together. The distance from take-off line to the heel is measured in inches. The best of three trials is recorded as the final score.

5. 50 Yard Dash

Purpose To measure speed.

Procedure The youth is asked to run 50 yards from the starting line and the time is recorded nearest to one-tenths of a second.

6. 600 Yard Run-Walk

Purpose To measure endurance.

Procedure The youth is asked to run and/or walk for 600 yards and the time is recorded in minutes and seconds. This can be run in an open field or the inside track of an athletic field, by marking the distances appropriately.

General Motor Fitness General motor fitness is an athlete’s general ability to perform different motor skills without getting too much fatigued. General motor ability consists of three items designed to test the motor ability of school and college boys and girls.

Test 1 Standing Broad Jump This test measures the explosive leg power. In this test, the student stands behind the restraining line, with feet several inches apart and the toes pointed straight ahead. The student should swing the arms forward, extend the knees and jump forward as far as possible.

Test 2 Zig – Zag run The materials, required are a stop-watch, five traffic cones, floor measuring tape and floor area of 30 feet by 50 feet. Cones are placed on the floor in a zig – zag manner. The objective is to measure the agility. The examine or the student stands at the starting point. On the signal ‘go’, he/she runs the course without touching the cones. The student continues to run the course three times and each time, the time is recorded with the help of a stopwatch. The score is the time recorded to the nearest tenth of a second. If the cones are moved during the run, then the trial is retaken.

Test 3 Medicine Ball Put The material required is medicine ball. The objective is to measure arm and shoulders girdle explosive strength. The student is required to put a 6 pound medicine ball as far as possible. Three trials are taken and the best score of the three is recorded. For boys the explosive strength throw test is for 3 kg medicine ball and for girls it is 1 kg.

Measurement of Cardiovascular Fitness Cardiovascular fitness is the ability of the heart and lungs to supply oxygen, rich blood to the working

muscle tissues and the ability of the muscles to use oxygen to produce energy for movements. This type of fitness is required to sustain physical activity and is essential for performing aerobic activities.

1. Harvard Step Test This test is also known as Aerobic Fitness test. It was developed by Brouha and others in 1943. It is used to measure the cardiovascular fitness or aerobic fitness by checking the recovery rate. Equipment Required Bench 20 inches high, for men and 16 inches for women, stopwatch and metronome.

2. Rockport Test This test also known as Rockport One Mile Test or Rockport Fitness Walking Test is used for testing cardiovascular fitness. It requires minimal equipment. This test consists of walking, which may be easy for middle-aged and older adults. This test tells us about the aerobic fitness of an individual. Equipment Required 400m track, stopwatch and weighing scale.

Computation of Fitness Index Fitness index is computed using the following formula:

𝐹𝐼 =𝐷𝑢𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑒𝑥𝑒𝑟𝑐𝑖𝑠𝑒 𝑖𝑛 𝑠𝑒𝑐𝑜𝑛𝑑𝑠 ∗ 100

(2 ∗ 𝑆𝑢𝑚 𝑜𝑓 𝑝𝑢𝑙𝑠𝑒 𝑐𝑜𝑢𝑛𝑡𝑠 𝑖𝑛 𝑟𝑒𝑐𝑜𝑣𝑒𝑟𝑦)

𝐹𝐼 =𝐷𝑢𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑒𝑥𝑒𝑟𝑐𝑖𝑠𝑒 𝑖𝑛 𝑠𝑒𝑐𝑜𝑛𝑑𝑠 ∗ 100

(5.5 ∗ 𝑃𝑢𝑙𝑠𝑒 𝑐𝑜𝑢𝑛𝑡 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 1 𝑎𝑛𝑑 1.5 𝑚𝑖𝑛𝑢𝑡𝑒𝑠)

Rikli and Jones- Senior Citizen Fitness Test Rikli and Jones prepared various physical fitness tests for senior citizens in 2001. Senior citizens can’t do exhaustive workouts however fitness is very important even in old age.

These tests are designed to access the functional fitness of older adults with the help of simple activities like getting up from a chair, walking, bending and stretching. These tests are safe, enjoyable and meet scientific standards of reliability and validity. That is why easy tests prepared for different body parts are given. These are:

1. Chair Stand Test for Lower Body Strength The Chair Stand Test is similar to a squat test to measure leg strength. This test is part of the senior fitness test protocol and is designed to test the functional fitness of seniors.

Purpose This test assesses leg strength and endurance of senior citizens.

Equipment Required A straight or folding chair without arm rests (seat 17 inches/ 44 cm high) and stopwatch.

2. Arm Curl Test for Upper Body Strength The Arm Curl Test is a test to measure the upper body strength of senior citizens or old people.

Purpose This test measures upper body strength and endurance.

Equipment Required 5 pound weight for women, 8 pound weight for men, a chair without arm rests, stopwatch.

3. Chair Sit and Reach Test for Lower Body Flexibility The Chair Sit and Reach Test is part of-the senior fitness test protocol, and is designed to test the functional fitness of seniors. It is a variation of the traditional sit and reach . flexibility test.

Purpose This test measures lower body. – flexibility.

Equipment Required Ruler, a chair with straight back or folding chair (17 inch/44 cm high).

4. Back Scratch Test for Upper Body Flexibility The shoulder stretch is a simple flexibility test to determine if the hands can be brought together behind the back particularly the shoulders. This test is part of the fitness programme as an alternative to the back saver sit and reach test.

Purpose This test measures upper arm and shoulder girdle flexibility.

Equipment Required None.

5. Eight Foot Up and Go Test for Agility The Eight Foot Up arid Go Test is a coordination and agility test’for the elderly-which is pair of the senior fitness test protocol.

Purpose This test measures speed, agility and balance while moving.

Equipment Required Stopwatch, straight back or folding chair ( seat 17 inches/44 height) cone rriarker, measuring tape, area clear of obstacles.

6. Six Minute Walk test for Aerobic Endurance The Six Minute Walk Test is a part, of the senior fitness test protocol arid is designed to test the functional fitness of seniors. It is an adaptation of the Cooper 12 – minutes run for people who use orthopaedic devices When walking as well as people who have difficulty in balancing.

Purpose This test measures aerobic fitness or aerobic endurance.

Equipment Required Measuring tape to mark out the track distances, stopwatch arid chairs positioned for testing.

of 25




ONLINE STUDY MATERIAL

SUBJECT-IP SESSION-2021-22

CLASS-XII

TOPIC: CSV WITH DATAFRAME AND PANDAS-II

DAY-1

NOTES

CHAPTER 07: WORKING WITH CSV FILES

INTRODUCTION

When you export data from Website, the files can be delivered in the following formats

1. CSV - COMMA SEPARATED VALUES

2. PSV - PIPE SEPARATED VALUES

3. TSV - TAB SEPARATED VALUES

1. CSV - COMMA SEPARATED VALUES

A CSV(Comma Separated Values) is a plain-text file format used to store tabular data such as a spreadsheet

or a database. It essentially stores a tabular data which comprises of numbers and text into plain text.

2. PSV - PIPE SEPARATED VALUES

When you export contact data and survey data from the Gateway eNews letter and Website systems, the

files will be delivered in a "pipe delimited" format. This means that the various columns are separated by

a pipe character.

3. TSV - TAB SEPARATED VALUES

A text file format that uses tab characters as separators between fields. The tab delimited format stores

information from a database or spreadsheet in the format of a tabular structure. Both Microsoft and Google

allow the user to convert a spreadsheet into tab delimited format.

WHAT IS A CSV FILE?

A CSV file is a type of plain text file that uses specific structuring to arrange tabular data. CSV is a

common format for data interchange as it's compact, simple and general. Many online services allow its users

to export tabular data from the website into a CSV file. Files of CSV will open into Excel, and nearly all



of 25

databases have a tool to allow import from CSV file. The standard format is defined by rows and columns

data. Moreover, each row is terminated by a newline to begin the next row. Also within the row, each column

is separated by a comma.

CSV (Comma-separated values) is a common data exchange format used by the applications to

produce and consume data. Some other well-known data exchange formats are XML, HTML, JSON

etc.

A CSV file is a simple text file where each line contains a list of values (or fields) delimited by commas.

Although the term "Comma" appears in the format name itself, but you will encounter CSV files where data is delimited using tab (\t) or pipe (|) or any other character that can be used as a delimiter.

The first line of the CSV file represents the header containing a list of column names in the file. The header is optional but highly recommended.

The CSV file is commonly used to represent tabular data. For example, consider the following table:

To retain the commas inside the Address field enclose it in double quotation marks, as follows:

Tabular data is represented by comma separated values

RollNo,Name,Age,Class,Sec

1023,Vishwa,14,VII,A

3078,Varun,16,X,B

3543,Gowtham,15,X,C

Every line of the file is called a record. And each record consists of fields that are separated

by commas which are also known as “delimiter” which is the default delimiter, others include pipe(|),

semicolon(;). Given below is a structure of a Normal CSV File separated by a comma

of 25

WHY IS CSV FILE FORMAT USED?

CSV is a plain-text file which makes it easier for data interchange and also easier to import onto

spreadsheet or database storage.

For example: You might want to export the data of a certain statistical analysis to CSV file and then

import it to the spreadsheet for further analysis. Overall it makes users working experience very

easy programmatically. Any language supporting a text file or string manipulation like Python can

work with CSV files directly.

CSV ADVANTAGES

CSV is human readable and easy to edit manually

CSV is simple to implement and parse

CSV is processed by almost all existing applications

CSV provides a straightforward information schema

CSV is faster to handle

CSV is smaller in size

CSV is considered to be standard format

CSV is compact. For XML you start tag and end tag for each column in each row. In CSV you

write the column headers only once.

CSV is easy to generate

CSV DISADVANTAGES

CSV allows to move most basic data only. Complex configurations cannot be imported and

exported this way

There is no distinction between text and numeric values

No standard way to represent binary data

Problems with importing CSV into SQL (no distinction between NULL and quotes)

Poor support of special characters

No standard way to represent control characters

Lack of universal standard

VIDEO-LINKS

https://www.youtube.com/watch?v= JzkDsPBy8&feature=youtu.be

https://www.youtube.com/watch?v=__JzkDsPBy8&feature=youtu.be

of 25

DAY-2

CSV FILE TYPES

1. CSV (COMMA DELIMITED)

2. CSV UTF-8 (COMMA DELIMITED)

3. CSV (MACINTOSH)

4. CSV (MS-DOS)

1. CSV (COMMA DELIMITED)

A comma-separated values file is a delimited text file that uses a comma to separate values.

Each line of the file is a data record. Each record consists of one or more fields, separated by

commas. Exporting to CSV uses a default encoding of Unicode (UTF-16le)

2. CSV UTF-8 (COMMA DELIMITED)

UTF-8 (Unicode Transformation Format -8 ) encoding, also referred to as "Unicode - UTF8" UTF-

8 encoded CSV files will work well with Accompa (Accompa is a leading cloud-based requirements

management software that helps you capture, track and manage requirements for your products &

projects). just English characters, or also contain non-English characters such as é, ç, ü

3. CSV (MACINTOSH)

CSV (Macintosh) .csv. Saves a workbook as a comma-delimited text file for use on

the Macintosh operating system, and ensures that tab characters, line breaks, and other characters

are interpreted correctly.

of 25

4. CSV (MS-DOS)

CSV (DOS).csv. Saves a workbook as a comma-delimited text file for use on

the Macintosh operating system, and ensures that tab characters, line breaks, and other characters

are interpreted correctly.

PYTHON CSV MODULE

Python uses a CSV package which is a part of the standard library, so you need not install it.

Python CSV package contains following functions:

Ser Functions Description

1 csv.field_size_limit It returns the maximum field size

2 csv.get_dialect Fetches the dialect associated with name

3 csv.list_dialects Displays all the registered dialects

4 csv.reader Read data from csv file

5 csv.register_dialect Dialect associated with a name

6 csv.writer Writes data to a csv file

7

csv.unregister_dialect

It deletes the dialect associated with the name

dialect registry

8 csv.QUOTE_ALL Quotes everything irrespective of the type

9 csv.QUOTE_MINIMAL Quotes special character field

10 csv.QUOTE_NONNUMERIC Quotes fields that are not numeral

11 csv.QUOTE_NONE Doesn’t quote anything in output

READING AND WRITING FILES

of 25

The csv module is used for reading and writing files. It mainly provides following classes and functions:

1. reader()

2. writer()

3. DictReader()

4. DictWriter()

1. READING A CSV FILE WITH reader()

The reader() function takes a file object and returns a _csv.reader object that can be used to iterate over the contents of a CSV file. The syntax of reader() function is as follows:

Syntax: reader(fileobj [, dialect='excel' [, **fmtparam] ]) -> _csv.reader

Argument Description

fileobj (required) It refers to the file object

dialect (optional) Dialect refers to the different ways of formatting the CSV document. By

default, the csv module uses the same format as Microsoft Excel. We will discuss

dialect in detail later in this post.

fmtparam (optional) It refers to the set of keyword arguments to customize the dialect (see the

next section).

Let's say we have following CSV file:

employees.csv

of 25

1 2 3 4

id,name,email,age,designation 1,John,[email protected],24,programmer 2,Bob,[email protected],34,designer 3,Mary,[email protected],43,sales

import csv

with open('employees.csv', 'rt') as f:

csv_reader = csv.reader(f)

for line in csv_reader:

print(line)

Here is how to read this CSV file:

Expected Output:

1 2 3 4

['id', 'name', 'email', 'age', 'designation'] ['1', 'John', '[email protected]', '24', 'programmer'] ['2', 'Bob', '[email protected]', '34', 'designer'] ['3', 'Mary', '[email protected]', '43', 'sales']

Notice that each line in the CSV file is returned as a list of strings.

To get the data from certain fields, you can use indexing. For example:

1 2 3 4 5 6 7

import csv with open('employees.csv', 'rt') as f:

csv_reader = csv.reader(f)

for line in csv_reader: print(line[0], line[1], line[2])

Expected Output:

1 2 3 4

id name email 1 John [email protected] 2 Bob [email protected] 3 Mary [email protected]

If you want to skip heading call the next() built-in function on the _csv.reader object and then loop over the remaining lines as usual.




of 25

VIDEO-LINKS


DAY-3

1 2 3 4 5 6 7 8 9

import csv

with open('employees.csv', 'rt') as f: csv_reader = csv.reader(f)

next(csv_reader) # skip the heading

for line in csv_reader: print(line[0], line[1], line[2])

Expected Output:

1 2 3

1 John [email protected] 2 Bob [email protected] 3 Mary [email protected]

CUSTOMIZING THE reader()

By default, the csv module works according to the format used by Microsoft excel, but you can also define your own format using something called Dialect.

The following are some additional arguments that you can pass to the reader() function to customize its working.

delimiter - It refers to the character used to separate values (or fields) in the CSV file. It defaults to

comma (,).

skipinitialspace - It controls how the space following the delimiter will be interpreted. If True , the

initial whitespaces will be removed. It defaults to False.

lineterminator - It refers to the character sequence used to terminate the line. It defaults to \r\n.

quotechar - It refers to the single character string that will be used to quote values if special characters

(like delimiter) appears inside the field. It defaults to ".

quoting - controls when quotes should be generated by the writer or recognized by the reader. It can

take one of the following constants:

o csv.QUOTE_MINIMAL means add quote only when required, for example, when a field contains either the quotechar or the delimiter. This is the default.

o csv.QUOTE_ALL means quotes everything regardless of the field type.





of 25

o csv.QUOTE_NONNUMERIC means quotes everything except integers and floats.

o csv.QUOTE_NONE means that do not quote anything on output. However, while reading quotes are included around the field values.

escapechar - It refers to the one-character string used to escape the delimiter when quoting is set

to QUOTE_NONE. It defaults to None.

doublequote - controls the handling of quotes inside fields. When True, two consecutive quotes are

interpreted as one during read, and when writing, each quote character embedded in the data is written

as two quotes. Let's workthrough some examples to better understand how these arguments work:

DELIMITER ARGUMENT

employees_pipe.csv

1 2 3 4

id|name|email|age|designation 1|John|[email protected]|24|programmer 2|Bob|[email protected]|34|designer 3|Mary|[email protected]|43|sales

This file uses pipe (|) character as a delimiter. Here is how to read this CSV file:

1 2 3 4 5 6 7

import csv with open('employees.csv', 'rt') as f:

csv_reader = csv.reader(f, delimiter='|')

for line in csv_reader: print(line)

Expected Output:

1 2 3 4

['id', 'name', 'email', 'age', 'designation'] ['1', 'John', '[email protected]', '24', 'programmer'] ['2', 'Bob', '[email protected]', '34', 'designer'] ['3', 'Mary', '[email protected]', '43', 'sales']

SKIPINITIALSPACE ARGUMENT

baseball_players.csv

1 2 3 4 5 6 7 8 9

"Name", "Team", "Position", "Height(inches)", "Weight(lbs)", "Age" "Adam Donachie", "BAL", "Catcher", 74, 180, 22.99 "Paul Bako", "BAL", "Catcher", 74, 215, 34.69 "Ramon Hernandez", "BAL", "Catcher", 72, 210, 30.78 "Kevin Millar", "BAL", "First Baseman", 72, 210, 35.43 "Chris Gomez", "BAL", "First Baseman", 73, 188, 35.71 "Brian Roberts", "BAL", "Second Baseman", 69, 176, 29.39 "Miguel Tejada", "BAL", "Shortstop", 69, 209, 30.77 "Melvin Mora", "BAL", "Third Baseman", 71, 200, 35.07




of 25

This CSV file contains spaces following the comma (,). To read this CSV file correctly, set skipinitialspace to True, as follows:

1 2 3 4 5 6 7

import csv with open('baseball_players.csv', 'rt') as f:

csv_reader = csv.reader(f, skipinitialspace=True)

for line in csv_reader: print(line)

Expected Output:

1 2 3 4 5 6 7 8 9

['Name', 'Team', 'Position', 'Height(inches)', 'Weight(lbs)', 'Age'] ['Adam Donachie', 'BAL', 'Catcher', '74', '180', '22.99'] ['Paul Bako', 'BAL', 'Catcher', '74', '215', '34.69'] ['Ramon Hernandez', 'BAL', 'Catcher', '72', '210', '30.78'] ['Kevin Millar', 'BAL', 'First Baseman', '72', '210', '35.43'] ['Chris Gomez', 'BAL', 'First Baseman', '73', '188', '35.71'] ['Brian Roberts', 'BAL', 'Second Baseman', '69', '176', '29.39'] ['Miguel Tejada', 'BAL', 'Shortstop', '69', '209', '30.77'] ['Melvin Mora', 'BAL', 'Third Baseman', '71', '200', '35.07']

WRITING CSV FILES WITH writer()

To write data to a CSV file we use the writer() function. It accepts the same argument as the reader() function but returns a writer object (i.e _csv.writer):

Syntax: writer(fileobj [, dialect='excel' [, **fmtparam] ]) -> csv_writer

ARGUMENT DESCRIPTION

fileobj (required) It refers to the file object

dialect (optional) Dialect refers to the different ways of formatting the CSV

document. By default, the csv module uses the same format as

Microsoft Excel. We will discuss dialect in detail later in this post.

fmtparam (optional) Formatting parameters, work same as the reader()'s function.

of 25

The writer instance provides the following two methods to write data:

Method Description

writerow(row) Writes a single row of data and returns the number of characters written.

The row must be a sequence of strings and number.

writerows(rows) Writes multiple rows of data and returns None. The rows must be a sequence.

VIDEO-LINKS


DAY-4

Example 1: Using writerow()


of 25

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

import csv header = ['id', 'name', 'address', 'zip'] rows = [

[1, 'Hannah', '4891 Blackwell Street, Anchorage, Alaska', 99503 ], [2, 'Walton', '4223 Half and Half Drive, Lemoore, California', 97401 ], [3, 'Sam', '3952 Little Street, Akron, Ohio', 93704], [4, 'Chris', '3192 Flinderation Road, Arlington Heights, Illinois',

62677], [5, 'Doug', '3236 Walkers Ridge Way, Burr Ridge', 61257],

] with open('customers.csv', 'wt') as f:

csv_writer = csv.writer(f)

csv_writer.writerow(header) # write header

for row in rows: csv_writer.writerow(row)

Example 2: Using writerows()

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17





csv_writer = csv.writer(f)


csv_writer.writerows(rows)

The output generated by both listing will be the same and it looks like this:

customers.csv

1 2 id,name,address,zip 1,Hannah,"4891 Blackwell Street, Anchorage, Alaska",99503

of 25

3 4 5 6

2,Walton,"4223 Half and Half Drive, Lemoore, California",97401 3,Sam,"3952 Little Street, Akron, Ohio",93704 4,Chris,"3192 Flinderation Road, Arlington Heights, Illinois",62677 5,Doug,"3236 Walkers Ridge Way, Burr Ridge",61257

Notice that only the address field is wrapped around double quotes. This is because by default the quoting argument is set to QUOTE_MINIMAL. In other words, fields will be quoted only when quotechar or delimiter appears in the data.

Let's say you want double quotes around all textual data. To achieve this, set quoting argument to QUOTE_NONNUMERIC.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17





csv_writer = csv.writer(f, quoting=csv.QUOTE_NONNUMERIC)



Expected Output:

customers.csv

1 2 3 4 5 6

"id","name","address","zip" 1,"Hannah","4891 Blackwell Street, Anchorage, Alaska",99503 2,"Walton","4223 Half and Half Drive, Lemoore, California",97401 3,"Sam","3952 Little Street, Akron, Ohio",93704 4,"Chris","3192 Flinderation Road, Arlington Heights, Illinois",62677 5,"Doug","3236 Walkers Ridge Way, Burr Ridge",61257

Now all the names and addresses have double quotes around them.

If you want double quotes around all fields regardless of whether quotechar or delimiter appears in the data or not, set quoting to csv.QUOTE_ALL.

1 2 3 4 5


[1, 'Hannah', '4891 Blackwell Street, Anchorage, Alaska', 99503 ],

of 25

6 7 8 9 10 11 12 13 14 15 16 17

[2, 'Walton', '4223 Half and Half Drive, Lemoore, California', 97401 ], [3, 'Sam', '3952 Little Street, Akron, Ohio', 93704], [4, 'Chris', '3192 Flinderation Road, Arlington Heights, Illinois',



csv_writer = csv.writer(f, quoting=csv.QUOTE_ALL)



Expected Output:

1 2 3 4 5 6

"id","name","address","zip" "1","Hannah","4891 Blackwell Street, Anchorage, Alaska","99503" "2","Walton","4223 Half and Half Drive, Lemoore, California","97401" "3","Sam","3952 Little Street, Akron, Ohio","93704" "4","Chris","3192 Flinderation Road, Arlington Heights, Illinois","62677" "5","Doug","3236 Walkers Ridge Way, Burr Ridge","61257"

Everything is double-quoted now.

It is important to note that when quoting is on (i.e quoting parameter has a value other than csv.QUOTE_NONE), the csv module uses the quotechar (which defaults to ") to quote field.

The following listing changes the quote character from double quote (") to a single quote (').

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17





csv_writer = csv.writer(f, quotechar="'")



Expected Output:

1 id,name,address,zip

of 25

2 3 4 5 6

1,Hannah,'4891 Blackwell Street, Anchorage, Alaska',99503 2,Walton,'4223 Half and Half Drive, Lemoore, California',97401 3,Sam,'3952 Little Street, Akron, Ohio',93704 4,Chris,'3192 Flinderation Road, Arlington Heights, Illinois',62677 5,Doug,'3236 Walkers Ridge Way, Burr Ridge',61257

In this case, the csv module uses the single quote (') instead of (") to quote fields containing quotechar or delimiter.

We can also turn off quoting all-together by setting quoting to csv.QUOTE_NONE. However, if you do that and delimiter character appears in the data then you will get an error like this:

VIDEO LINKS:



of 25

DAY-5

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17

import csv

header = ['id', 'name', 'address', 'zip'] rows = [



]

with open('customers.csv', 'wt') as f: csv_writer = csv.writer(f, quoting=csv.QUOTE_NONE)



Expected Output:

1 2 3 4

Traceback (most recent call last): ... csv_writer.writerows(rows) _csv.Error: need to escape, but no escapechar set

The problem is that the address field contains embedded commas (,) and since we have turned off the ability to quote fields, the csv module doesn't know how to escape them properly.

This where the escapechar argument comes into play. It takes a one-character string that will be used to escape the delimiter when the the quoting is turned off (i.e quoting=csv.QUOTE_NONE).

The following listing set the escapechar to backslash (\).

1 2 3 4 5 6 7 8 9 10 11 12 13 14





csv_writer = csv.writer(f, quoting=csv.QUOTE_NONE, escapechar='\\')

of 25

15 16 17



Expected Output:

1 2 3 4 5 6

id,name,address,zip 1,Hannah,4891 Blackwell Street\, Anchorage\, Alaska,99503 2,Walton,4223 Half and Half Drive\, Lemoore\, California,97401 3,Sam,3952 Little Street\, Akron\, Ohio,93704 4,Chris,3192 Flinderation Road\, Arlington Heights\, Illinois,62677 5,Doug,3236 Walkers Ridge Way\, Burr Ridge,61257

Notice that the commas (,) in the address field is escaped using the backslash (\) character.

You should now have a good understanding of various formatting arguments and the context in which they are used with the reader() and writer() function. In the next section will see some other ways to read and write data.

READING A CSV FILE WITH DictReader

DictReader works almost exactly like reader() but instead of retuning a line as a list, it returns a dictionary. Its syntax is as follows:

Syntax:: DictReader(fileobj, fieldnames=None, restkey=None, restval=None, dialect='excel', **fmtparam)


fileobj (required) It refers to the file object.

fieldnames (optional) It refers to the list of keys that will be used in the returned dictionary

in order. If omitted, the field names are inferred from the first row of the CSV

file.

restkey (optional) If the row has more fields than specified in the fieldnames parameter,

then the remaining fields is stored as a sequence keyed by the value

of restkey argument.

restval (optional) It provides value to fields which are missing from the input.

of 25


dialect (optional) Dialect refers to the different ways of formatting the CSV document.

By default, the csv module uses the same format as Microsoft excel. We will

discuss dialect in detail later in this post.

fmtparam It refers to formatting arguments and works exactly like reader() and writer().

Let's take some examples:

Example 1:

customers.csv

1 2 3 4 5 6

id,name,address,zip 1,Hannah,4891 Blackwell Street\, Anchorage\, Alaska,99503 2,Walton,4223 Half and Half Drive\, Lemoore\, California,97401 3,Sam,3952 Little Street\, Akron\, Ohio,93704 4,Chris,3192 Flinderation Road\, Arlington Heights\, Illinois,62677 5,Doug,3236 Walkers Ridge Way\, Burr Ridge,61257

1 2 3 4 5 6 7

import csv with open('customers.csv', 'rt') as f:

csv_reader = csv.DictReader(f, escapechar='\\')

for row in csv_reader: print(row)

Expected Output:

1 2 3 4 5 6

{'id': '1', 'name': 'Hannah', 'zip': '99503', 'address': '4891 Blackwell Street, Anchorage, Alaska'} {'id': '2', 'name': 'Walton', 'zip': '97401', 'address': '4223 Half and Half Drive, Lemoore, California'} {'id': '3', 'name': 'Sam', 'zip': '93704', 'address': '3952 Little Street, Akron, Ohio'} {'id': '4', 'name': 'Chris', 'zip': '62677', 'address': '3192 Flinderation Road, Arlington Heights, Illinois'} {'id': '5', 'name': 'Doug', 'zip': '61257', 'address': '3236 Walkers Ridge Way, Burr Ridge'} **Note:** Order of keys in the result may vary. Since dictionary doesn't preserve the order of elements.

In this case, the field names are inferred from the first line (or header) of the CSV file.

Example 2: Using fieldnames parameter

of 25

1 2 3 4 5

1,Hannah,4891 Blackwell Street\, Anchorage\, Alaska,99503 2,Walton,4223 Half and Half Drive\, Lemoore\, California,97401 3,Sam,3952 Little Street\, Akron\, Ohio,93704 4,Chris,3192 Flinderation Road\, Arlington Heights\, Illinois,62677 5,Doug,3236 Walkers Ridge Way\, Burr Ridge,61257

This CSV file has no header. So we have to provide field names via the fieldnames parameter.

1 2 3 4 5 6 7 8 9


fields = ['id', 'name', 'address', 'zip']

csv_reader = csv.DictReader(f, fieldnames=fields, escapechar='\\')


Expected Output:

1 2 3 4 5

{'name': 'Hannah', 'zip': '99503', 'id': '1', 'address': '4891 Blackwell Street, Anchorage, Alaska'} {'name': 'Walton', 'zip': '97401', 'id': '2', 'address': '4223 Half and Half Drive, Lemoore, California'} {'name': 'Sam', 'zip': '93704', 'id': '3', 'address': '3952 Little Street, Akron, Ohio'} {'name': 'Chris', 'zip': '62677', 'id': '4', 'address': '3192 Flinderation Road, Arlington Heights, Illinois'} {'name': 'Doug', 'zip': '61257', 'id': '5', 'address': '3236 Walkers Ridge Way, Burr Ridge'}

Example 3: Using restkey parameter

1 2 3 4 5


1 2 3 4 5 6 7 8 9 10


fields = ['id','name',]

csv_reader = csv.DictReader(f, fieldnames=fields, restkey='extra', escapechar='\\')


Expected Output:

of 25

1 2 3 4 5

{'id': '1', 'name': 'Hannah', 'extra': ['4891 Blackwell Street, Anchorage, Alaska', '99503']} {'id': '2', 'name': 'Walton', 'extra': ['4223 Half and Half Drive, Lemoore, California', '97401']} {'id': '3', 'name': 'Sam', 'extra': ['3952 Little Street, Akron, Ohio', '93704']} {'id': '4', 'name': 'Chris', 'extra': ['3192 Flinderation Road, Arlington Heights, Illinois', '62677']} {'id': '5', 'name': 'Doug', 'extra': ['3236 Walkers Ridge Way, Burr Ridge', '61257']}

Notice that the address and zip code are now stored as a sequence keyed by value extra.

Example 4: Using restval

1 2 3 4 5


1 2 3 4 5 6 7 8 9 10


fields = ['id','name', 'address', 'zip', 'phone', 'email'] # two extra fields

csv_reader = csv.DictReader(f, fieldnames=fields, restkey='extra', restval='NA', escapechar='\\')


Expected Output:

1 2 3 4 5

{'id': '1', 'name': 'Hannah', 'email': 'NA', 'phone': 'NA', 'address': '4891 Blackwell Street, Anchorage, Alaska', 'zip': '99503'} {'id': '2', 'name': 'Walton', 'email': 'NA', 'phone': 'NA', 'address': '4223 Half and Half Drive, Lemoore, California', 'zip': '97401'} {'id': '3', 'name': 'Sam', 'email': 'NA', 'phone': 'NA', 'address': '3952 Little Street, Akron, Ohio', 'zip': '93704'} {'id': '4', 'name': 'Chris', 'email': 'NA', 'phone': 'NA', 'address': '3192 Flinderation Road, Arlington Heights, Illinois', 'zip': '62677'} {'id': '5', 'name': 'Doug', 'email': 'NA', 'phone': 'NA', 'address': '3236 Walkers Ridge Way, Burr Ridge', 'zip': '61257'}

In this case, we have specified field two extra fields: phone and email. The values for extra fields is provided by the restval argument.

of 25

Writing CSV files with DictWriter()

The DictWriter object writes a dictionary to a CSV file. Its syntax is as follows:

Syntax: DictWriter(fileobj, fieldnames, restval='', extrasaction='raise', dialect='excel', **fmtparam)

Argument Description

fileobj It refers to the file object

fieldnames It refers to the field names and the order in which they will be written the file.

restval It provides the missing value for the keys which doesn't exist in the dictionary.

extrasaction It controls what action to take if the dictionary contains a key, that is not found in

the fieldnames argument. By default, extrasaction is set to raise, which means an

exception will be raised in such an event. If you want to ignore the extra values

set extrasaction to ignore.

The DictWriter provides the following three methods to write data.

Method Description

writeheader() Writes the header (i.e fieldnames) to the CSV file and returns None.

writerow(row) Writes a single row of data and returns the number of characters written.

The row must be a sequence of strings and number.

writerows(rows) Writes multiple rows of data and returns None. The rows must be a sequence.

Let's take some examples:

Example 1:

import csv

of 25

header = ['id', 'name', 'address', 'zip']

rows = [

{'id': 1, 'name': 'Hannah', 'address': '4891 Blackwell Street, Anchorage, Alaska', 'zip': 99503 },

{'id': 2, 'name': 'Walton', 'address': '4223 Half and Half Drive, Lemoore, California', 'zip': 97401 },

{'id': 3, 'name': 'Sam', 'address': '3952 Little Street, Akron, Ohio', 'zip': 93704 },

{'id': 4, 'name': 'Chris', 'address': '3192 Flinderation Road, Arlington Heights, Illinois', 'zip': 62677},

{'id': 5, 'name': 'Doug', 'address': '3236 Walkers Ridge Way, Burr Ridge', 'zip': 61257},

]

with open('dictcustomers.csv', 'wt') as f:

csv_writer = csv.DictWriter(f, fieldnames=header)

csv_writer.writeheader() # write header


Expected Output:

dictcustomers.csv

1 2 3 4 5 6

id,name,address,zip 1,Hannah,"4891 Blackwell Street, Anchorage, Alaska",99503 2,Walton,"4223 Half and Half Drive, Lemoore, California",97401 3,Sam,"3952 Little Street, Akron, Ohio",93704 4,Chris,"3192 Flinderation Road, Arlington Heights, Illinois",62677 5,Doug,"3236 Walkers Ridge Way, Burr Ridge",61257

Example 2: Using restval

1 2 import csv

of 25

3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

header = ['id', 'name', 'address', 'zip', 'email'] # an extra field email rows = [





{'id': 5, 'name': 'Doug', 'address': '3236 Walkers Ridge Way, Burr Ridge', 'zip': 61257}, ] with open('dictcustomers.csv', 'wt') as f:

csv_writer = csv.DictWriter(f, fieldnames=header, restval="NA")



Expected Output:

dictcustomers.csv

1 2 3 4 5 6

id,name,address,zip,email 1,Hannah,"4891 Blackwell Street, Anchorage, Alaska",99503,NA 2,Walton,"4223 Half and Half Drive, Lemoore, California",97401,NA 3,Sam,"3952 Little Street, Akron, Ohio",93704,NA 4,Chris,"3192 Flinderation Road, Arlington Heights, Illinois",62677,NA 5,Doug,"3236 Walkers Ridge Way, Burr Ridge",61257,NA

In this case, the value of email field is missing from the dictionaries. As s result, the value of restval will be used for the email field.

Example 3: Using extrasaction

1 2 3 4 5 6 7 8 9 10 11

import csv header = ['id', 'name', 'address'] # notice zip is missing rows = [




of 25

12 13 14 15 16 17 18 19 20 21 22 23 24


{'id': 5, 'name': 'Doug', 'address': '3236 Walkers Ridge Way, Burr Ridge', 'zip': 61257}, ]

with open('dictcustomers.csv', 'wt') as f:

csv_writer = csv.DictWriter( f, fieldnames=header, restval="NA", extrasaction='ignore' # ignore extra values in the

dictionary )



Here, the dictionary contains an extra key named zip which is not present in the header list. To prevent the exception from being raised we have set extrasaction to ignore.

Expected Output:

dictcustomers.csv

1 2 3 4 5 6

id,name,address 1,Hannah,"4891 Blackwell Street, Anchorage, Alaska" 2,Walton,"4223 Half and Half Drive, Lemoore, California" 3,Sam,"3952 Little Street, Akron, Ohio" 4,Chris,"3192 Flinderation Road, Arlington Heights, Illinois" 5,Doug,"3236 Walkers Ridge Way, Burr Ridge"

VIDEO LINKS:



bishopscott - bishop scott boys school

Documents