The basics of Python programming

Python has a number of language requirements and conventions, which allow for the control of modules and the structuring of code. Following are a number of important basic concepts which will be used throughout this book, and when crafting scripts for use with geospatial analysis.

To test these examples, open the IDLE (Python GUI) program from the Start Menu/ArcGIS/Python2.7 folder after installing ArcGIS for Desktop. It has a built-in "interpreter" or code entry interface, indicated by the triple chevron >>> and a blinking cursor. To create a script in IDLE to save your code, click on to the File menu and then click New File. Save any script with a .py extension. Otherwise, just enter commands into the interpreter and push Enter to execute or add the next line.