functionality differences between arcgis and...
TRANSCRIPT
Functionality differences between ArcGIS and QGIS
Ayesha Rana Anwar
Department of Space Science,
University of the Punjab, Lahore
Sequence
• Introduction
• Open Source Software and Commercial Software
• QGIS and ArcGIS
• Data and Methodology
• Topological Functionalities
• Cartographic Capabilities
• Network Analysis
• Results and discussions
• Conclusion
Introduction
Open Source Software
• Easy access to its source code.
• Source code can be read, modified and improved by developer or volunteer.
• Low cost or free software.
• Doesn’t need expensive hardware or software to run it.
• Open source software includes:
• GRASS GIS
• MapWindow GIS
• QGIS
• SAGA GIS etc
Commercial Software
• Not freely available.
• License is restricted.
• Source codes are kept in secret from external people.
• Source code can be changed only by the company or person who developed it.
• The restrictions are imposed on it through a document called EULA (End-user license agreements).
• The results are reliable.
Commercial Software
• Commercial software includes:
• AutoCAD
• ArcGIS
• ArcWeb etc.
QGIS
• It is open source software.
• It is freely available. • It can be installed on
different operating systems.
• It is not licensed software.
• It is developed by all over the world programmers.
VS ArcGIS
• It is commercial software.
• It is not freely available.
• It can only be installed on window system.
• It is single user licensed software.
• It is deployed in secure environment of Esri.
Data and Methodology
Three functionality differences between ArcGIS and QGIS discussed here
• Topological Functionalities
• Cartographic capabilities
• Network analysis.
Dataset Format Source
Land marks of Lahore Shapefile ESRI
Roads of Lahore Shapefile ESRI
Area of Lahore Shapefile ESRI
Pakistan’s Provinces boundary
Shapefile DIVA GIS
Topological Functionalities
• Topology expresses the spatial relationships between adjacent vector features in same shapefile or different shapefiles.
• Topological rules are used for detecting errors and correcting digitized data.
• Necessary for some types of spatial analysis.
• Different Topological rules in ArcGIS and QGIS.
Topological Functionalities
• Shapefile of Pakistan’s provinces boundary was used to compare topological functionalities of ArcGIS and QGIS.
• “must not have gaps” topological rule was used.
Topology Topology result in ArcGIS Environment.
Topology result in QGIS Environment.
Cartographic Capabilities
• A map is scaled representation of cultural and natural features on earth.
• To compare mapping capabilities, maps were made in both Esri’s ArcGIS environment and QGIS environment.
Mapping
Basemap of Lahore in ArcGIS Environment.
Basemap of Lahore in QGIS Environment.
Network Analysis
• A network is combination of nodes and arcs.
• Network analysis is set of analysis techniques used with network.
• Many applications in GIS used network analysis.
• To compare network analysis “shortest path” was measured in both ArcGIS and QGIS.
Network Analysis Shortest Distance in ArcGIS Environment.
Shortest Distance in QGIS Environment.
Results and Discussion
Topology results in ArcGIS Environment.
• To apply topology have to make database.
• Rings in Baluchistan and KPK marked as errors.
• Value of cluster tolerance in arc map is limited to 0.0000009. So very small gaps along AJK, GB and Kashmir are not marked as errors.
Topological functionalities results
Topology results in QGIS Environment.
• Topology can simply apply by “Topology Checker Plugin”.
• In QGIS topology "must not have gaps" didn’t consider ring polygons/ donuts polygons as topological errors.
• Very small gaps along AJK, GB and Kashmir are marked as errors.
• Cluster tolerance doesn’t effect the topological errors. QGIS topology checker is not good enough.
Topological functionalities results
Basemap of Lahore in ArcGIS Environment.
• There are more native
cartographic output options with ArcGIS.
• Different data frames can be added and linked.
• ArcGIS software has lot of advanced mapping functionalities.
Cartographic capabilities results
Basemap of Lahore in QGIS Environment.
• Different data frames can’t be linked.
• QGIS doesn’t have advanced mapping functionalities as compare to ArcGIS.
Cartographic capabilities results
Network analysis results
The resultant output was almost same but one can calculate the “shortest path” in QGIS software easily with the help of “Road Graph” plugin but in ArcGIS one can’t calculate without making geodatabase.
Shortest path in ArcGIS Shortest path in QGIS
Conclusion • QGIS is an open source software and it is easy to access as
compare to commercial software ArcGIS.
• Although a continuous development of plugins in QGIS but at present time it is not as much developed as ArcGIS is.
• QGIS has less processing time and better rendering capabilities.
• ArcGIS is preferred on QGIS because ArcGIS has better spatial topological analytical capabilities than QGIS.
• In QGIS topological results are not effected by the cluster tolerance.
• ArcGIS software has lot of advanced mapping functionalities than QGIS software like maplex labeling engine.
• ArcGIS has more reliable results than QGIS.
• In ArcGIS and QGIS environments shortest route can be calculated by using network analyst and road graph plugin respectively.
• ArcGIS other than shortest and fastest route generation there are many other modules available which are not present in QGIS software, i.e;
• New Surface Area
• Closet Facility
• New OD Cost Matrix
• New Vehicle Routing Problem
• New Location-Allocation
Closet facility in ArcGIS calculated in ArcGIS Environment
Thank you for your kind attention