introduction to the sgplot procedure - uncw …people.uncw.edu/blumj/stt592/ppt/introduction to the...

Introduction to the

SGPLOT Procedure

SAS SG Procedures

SG refers to “Statistical Graphics” and is an offshoot of

the recent introduction of special ODS graphics to

SAS/STAT procedures.

They may be better thought of as “template-based”

graphics procedures as opposed to “device-based”

procedures like GPLOT and GCHART.

In fact, the SG procedures can be thought of as

alternate ways to use various graph templates—results

can be duplicated with PROC TEMPLATE and PROC

SGRENDER.

SG procedures deliver directly to a specific graphics file

format (png by default), rather than to a SAS window.

SGPLOT

SGPLOT allows for an extensive collection of graphs (and

associated options to be selected).

Some choices:

Distributional

proc sgplot data=mysas.fish;

histogram hg;

where hg lt 2;

run;

quit;

Histogram Options

dataskin=


histogram hg/dataskin=pressed;

where hg lt 2;

run;

quit;

Histogram Options

dataskin=


histogram hg/dataskin=pressed;

where hg lt 2;

run;

quit;

Options include: None,

Crisp, Gloss, Matte,

Pressed and Sheen

Histogram Options

Bin options: binstart=,binwidth=


histogram hg/binstart=0 binwidth=0.2;

where hg lt 2;

run;

quit;

Histogram Options

Bin options: nbins=


histogram hg/nbins=6;

where hg lt 2;

run;

quit;

Histogram Options

Vertical Scale: Scale=


histogram hg/scale=count;

where hg lt 2;

run;

quit;

Histogram Options

Vertical Scale: Scale=


histogram hg/scale=count;

where hg lt 2;

run;

quit;

Percent is the default,

proportion is also available.

Other Distributional Graphs

density statement


density hg;

where hg lt 2;

run;

quit;


density statement


density hg;

where hg lt 2;

run;

quit;

Normal is the default,

parameters are estimated

from the data.


type= allows you to change to kernel estimate


density hg/type=kernel;

where hg lt 2;

run;

quit;


type= allows you to change to kernel estimate



where hg lt 2;

run;

quit;

Both Normal and Kernel

allow for additional options.

Combining Graphs

SGPLOT allows multiple graphs to be selected and, by default,

works in layers.

Try:


histogram hg/dataskin=sheen;

density hg;


where hg lt 2;

run;

quit;

Combining Graphs



density hg;


where hg lt 2;

run;

quit;

Order Matters


density hg;



where hg lt 2;

run;

quit;

Order Matters


density hg;



where hg lt 2;

run;

quit;

This is drawn first,

behind/under the histogram.

Combining Graphs—Useful Options

Some SGPLOT statements control styles of various graph elements

through various options.

Try:



density hg;


keylegend / location=inside position=topleft

across=1 title='Density Type'

titleattrs=(family='Arial Black' color=blue);

where hg lt 2;

run;

quit;





Chooses where the

legend is displayed





Can specify across or down to

set number of rows or columns.

You should pick one or the other.





Can create a title for

your legend.





Attributes can be set for

various character

elements like the title.

Several “attrs” (attributes) options will

be available.

A Few Other Useful Statements & Options

Axes can be altered with specific SGPLOT statements and options.

xaxis:



density hg;





xaxis minor minorcount=2 offsetmin=0

valueattrs=(family='Georgia' color=cx5555FF size=12pt);

where hg lt 2;

run;

quit;




Establish the presence of

minor ticks and how many

appear between major ticks




Distance from axis to lowest

major tick. Must be between 0

and 1, taken as a proportion of

available space

offsetmax= is also

available




Another “attrs” option, this controls

the value text—values at major ticks.


yaxis, too:


histogram hg/dataskin=sheen scale=proportion;

density hg;







yaxis offsetmax=0 values=(0 to .25 by 0.025) valuesformat=percent8.1

display=(nolabel);

where hg lt 2;

run;

quit;

This change will be

applied to the y-axis for all

three overlayed figures



display=(nolabel);

Value range can be set—

these are now decimals



display=(nolabel);

But a format for them can

be chosen (like percent).



display=(nolabel);

So that axis label is no

longer necessary.

Exercises

Using the projects data set, see if you can make this overlay (some

new options for density and histogram, no other statements yet).

Exercises

Now work on the axes a bit.

Exercises

And a little more…

introduction to the sgplot procedure - uncw …people.uncw.edu/blumj/stt592/ppt/introduction to the...

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