GIS Programming - Module 3 - Python Fundamentals Part 2

Results from the Interactive Window for the Module 3 Scripts

In the second week of learning the fundamentals of Python, we examined a script with an if conditional statement, and identified and corrected a couple of errors that were preventing the script from running.


We also wrote two scripts of our own.  The first script created a list of 20 randomly-generated numbers,with values of 0 to 10, then printed the whole list.








In the second script, we specified one "unlucky" number, then had the script remove all instances of that number, if it was there, from the list we'd made in the previous step.  We also had the script print messages that stated if the number was in the list, or not, and if so, how many times.  At the end, the new list without the unlucky number was printed.

Here are some notes from my Process Summary for this week.  This describes generally how the unlucky number can be removed from the script in the last block.

Removing numbers from the list. 

1.      For this part of the code, you already have the list with the random numbers appended into it.

2.      A variable has already been assigned to the unlucky number.

3.      All instances of the unlucky number are removed from the list with a while loop. 

4.      As long as the list still contains instances of the unlucky number, the while loop will continue to repeat and remove the numbers; this is the condition. 

5.      The indented statement within the while loop that actually removes the number is the remove method: the object is the list, and the argument is the variable assigned to the unlucky number. 

6.      In my script, the method is: SeaseList.remove (unlucky).

This script has a system argument: the user must input the unlucky number variable in the Run Script box.