GIS Programming Module 1 – Python Environments & Flowcharts

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Module 1 examines “The Zen of Python” which is a poem by Tim Peters a software engineer. This poem can be seen by typing “import this” into any Python interpreter and describes what it means to write Python code.

“The Zen of Python” is the principals or guidelines on how programmers should write code. These principles suggest to me that we should write code in a way that is easy to read and understand, even though the code may be complicated. I see this as writing code that is modular where the complexity can be broken down into smaller functions that do a specific task. Complexity can also be handled by simplifying the code, by finding ways to reduce the number of lines it takes to accomplish the same task. We should follow these principles not only for others who might later need to interpret the code, but for ourselves to help us in debugging and future alterations. It is up to the programmer to write code that provides the required functionality, but they should make a conscious effort to maintain readability and reduce complexity wherever possible. 

One of the tasks of Module 1 was to create a flowchart of a program that converts 3 radians to degrees and print the result. The formula for converting radians to degrees was given as

               degrees = radians*180 / pi.

I first created the pseudocode and then created the flowchart using draw.io.


The first part of Module 1 was to create all the folders needed for this course inside the S:\ drive, which is the student’s files folder on Argo.  I completed the task by logging into ArgoApps Lite and running the Python script file CreateModFolders.py using the IDLE. The results of running the script created the main class folder S:\GISProgramming and all the subfolders needed for all 6 modules. The subfolders Data, Results, and Scripts were created inside each of the Module folders. The process was straight forward. The only issue I had was knowing where to copy the CreateModFolders.py script. I realized after examining the code that it really did not matter where the script was executed since the path S:\GISProgramming was hard coded in the script.

 

The second part of Module 1 was answering the questions in the Process Summary. I utilized the course book “Python Scripting for ArcGIS Pro” and internet resources to answer questions Q1, Q2, Q3, and Q5. These resources helped me better understand the similarities and differences between IDLE and ArcGIS Notebooks. For questions Q4, I utilized Chapter 3 from Agarwal to better understand how to write pseudocode and create a Flowchart of the code. I downloaded Draw.io to create the flowchart.


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