Julieta's GIS Blog

In this module we learned how to perform geoprocessing tasks using Python and the syntax for using tools and toolboxes from ArcMap. The lab required to perform three geoprocessing tasks: Add XY coordinates to a shape file. Create a buffer of 1000 meters for the shape file. Dissolve the buffer into a separate feature. Each task also had to print the messages form every tool using the GetMessages() function.  Below is a simple model of what was done in the script. This interactive window shows the script's final output messages.

This week we practiced several types of geoprocessing techniques, including batch processing, making new tools with ModelBuilder, and converting those tools into Scripts and Script tools. For the lab part, we had to create a model and a script tool to perform two geoprocessing tasks: first to run a query of soils with a specific attribute, and then to erase those soils and produce a final soil shape file. The final model clips, queries, then erases and produces three new shape files (soil_clip, soil_select, and soil_final) as seen below. The final outcome on the map looks like this: The Soil shape file has been clipped to display Soils that fall within the Basin shape file. Soils with the attribute 'Not prime farmland' have been selected and removed from the final Soil shape file. 

This first peer-review looks at  Geoprocessing tool to model beach erosion due to storms: application toFaro beach (Portugal) . The paper is on a geoprocessing tool used to model beach erosion, specifically applied to Faro beach in South Portugal. This tool would assess beach erosion due to storms using two computational modules in order to determine whether the geoprocessing tool would be useful in helping predict storm impact along Faro beach. Its final conclusion was that the tool does work after several testing procedures to assure that the tool could be relied upon. It appears to be original work published on the Journal of Coastal Research, Special Issue 64, 2011 by faculty from Center for Marine and Environmental Research (CIMA) at Algarve University and University of Lisbon in Portugal. The science and testing procedures described were clear and concise. Sufficient data information is provided to follow along their methods of testing the geoprocessing tool. The pape...

In this module we explored numerous methods for debugging which included examining error messages, the addition of print statements, and practiced more selective commenting out of code. We also reviewed approaches to basic error-handling, coding errors in Python and ArcGIS geoprocessing. The lab required to debug 3 different scripts: The first required to fix the errors in the script. In the end, it would print the field names for a shape file. The second script also had errors to fix and would produce a list of layers in an AcMap file. The final script also had errors and consisted of 2 parts. Instead of fixing them I needed to include an exception for it to print the error in Part A and then continue to run the script in Part B.

Continuing with fundamentals, we delved into learning to use conditional statements to perform different actions in differing situations, for and while loops to repeat processes, and also get our hands on practicing how to identify and fix errors in Python. For this lab, I completed an unfinished Python script for a dice game, corrected errors in it, then added two new blocks of code requiring to print statements for certain conditions and remove a number from a randomly generated number list. Below is the final outcome.