Python in ArcGIS Pro 1

1.1   Let’s try Calculate Field

1. Download georgia-wind-50m.zip from GIS data and add the Shapefile to a new map.
2. Can you find the Calculate Field tool?
3. There are seven categories of the wind speed for the state of Georgia in the GRIDCODE field.
4. We want to convert these codes to the ranges of miles per hour (WindMph).
   • Check Georgia 50m WPC Map.pdf for the ranges.
5. In the text box next to “=”, type get_wind_mph(!GRIDCODE!).
6. In the code block text box, type the following code and hit Run.

   # a hash sign (#) starts comments that are ignored by Python; define a function
   # called get_wind_mph that takes one argument called gridcode; a function is a
   # group of statements that do some tasks to achieve a common goal
   def get_wind_mph(gridcode):
     # you need to indent any code blocks consistently
     # you're inside the function code block
     if gridcode == 1:
       # you're inside an if code block; use double equal signs for equal
       # comparisons and a single equal sign for assignments; if gridcode
       # is 1, return "0.0-12.5" and exit the function
       return "0.0-12.5" # double quotes create a string (text)
     elif gridcode == 2: # else if gridcode is 2, return "12.5-14.3"
       return "12.5-14.3"
     elif gridcode == 3:
       return "14.3-15.7"
     elif gridcode == 4:
       return "15.7-16.8"
     elif gridcode == 5:
       return "16.8-17.9"
     elif gridcode == 6:
       return "17.9-19.7"
     else: # else return ">19.7"
       return ">19.7"