GEOG 485:
GIS Programming and Automation

2.2.4 Other sources of help


Besides the above approaches, there are many other places you can get help. A few of them are described below. If you're new to programming, just knowing that these resources exist and how to use them can help you feel more confident. Find the ones that you prefer and return to them often. This habit will help you become a self-sufficient programmer and will improve your potential to learn any new programming language or technology.

Drawing on the resources below takes time and effort. Many people don't like combing through computer documentation, and this is understandable. However, you may ultimately save time if you look up the answer for yourself instead of waiting for someone to help you. Even better, you will have learned something new from your own experience, and things you learn this way are much easier to remember in the future.

Sources of help

Search engines

Search engines are useful for both quick answers and obscure problems. Did you forget the syntax for a loop? The quickest remedy may be to Google "for loop python" or "while loop python" and examine one of the many code examples returned. Search engines are extremely useful for diagnosing error messages. Google the error message in quotes and you can read experiences from others who have had the same issue. If you don't get enough hits, remove the quotes to broaden the search.

One risk you run from online searches is finding irrelevant information. Even more dangerous is using irrelevant information. Research any sample code to make sure it is applicable to the version of Python you're using. Some syntax in Python 3.x is different from the Python 2.x that you're using in this course.

Esri online help

Esri maintains their entire help system online, and you'll find most of their scripting topics in the sections Python and ArcPy.

Another section, which you should visit repeatedly, is the Tool Reference, which describes every tool in the toolbox and contains Python scripting examples for each. If you're having trouble understanding what parameters go in or out of a tool, or if you're getting an error back from the geoprocessing framework itself, try the Tool Reference before you do a random Internet search. You will have to visit the Tool Reference in order to be successful in some of the course projects and quizzes.

Python online help

The official Python documentation is available online. Some of it gets very detailed and takes the tone of being written by programmers for programmers. The part you'll probably find most helpful is the Python Standard Library reference, which is a good place to learn about Python's modules such as "os", "csv", "math," or "random."

Printed books, including your textbook

Programming books can be very hit or miss. Many books are written for people who have already programmed in other languages. Others proclaim they're aimed at beginners, but the writing or design of the book may be unintuitive or difficult to digest. Before you drop $40 on a book, try to skim through it yourself to see if the writing generally makes sense to you (don't worry about not understanding the code--that will come along as you work through the book).

The course text Python Scripting for ArcGIS is a generally well-written introduction to just what the title says: working with ArcGIS using Python. There are a few other books that have started to appear on this subject and I anticipate there will be more. If you've struggled with the material, or if you want to do a lot of scripting in the future, I may recommend picking up one of these. Your textbook can come in handy if you need to look at a very basic code example, or if you're going to use a certain type of code construct for the first time and you want to review the basics before you write anything.

A good general Python reference is Learning Python by Mark Lutz. We previously used this text in Geog 485 before there was a book about scripting with ArcGIS. It covers beginning to advanced topics, so don't worry if some parts of it look intimidating.

Esri forums and other online forums

The Esri forums are a place where you can pose your question to other Esri software users, or read about issues other users have encountered that may be similar to yours. There is a Python Esri forum that relates to scripting with ArcGIS, and also a more general Geoprocessing Esri forum you might find useful.

Before you post a question on the Esri forums, do a little research to make sure the question hasn't been answered already, at least recently. I also suggest that you post the question to our class forums first, since your peers are working on the same problems and you are more likely to find someone who's familiar with your situation and has found a solution.

There are many other online forums that address GIS or programming questions. You'll see them all over the Internet if you perform a Google search on how to do something in Python. Some of these sites are laden with annoying banner ads or require logins, while others are more immediately helpful. Stack Exchange is an example of a well-traveled technical forum, light on ads, that allows readers to promote or demote answers depending on their helpfulness. One of its child sites, GIS Stack Exchange, specifically addresses GIS and cartography issues.

If you do post to online forums, be sure to provide detailed information on the problem and list what you've tried already. Avoid posts such as "Here's some code that's broken and I don't know why" followed by dozens of lines of pasted-in code. State the problem in a general sense and focus on the problem code.

People on online forums are generally helpful, but expect a hostile reception if you make them feel like they are doing your academic homework for you. Also, be aware that posting or copying extensive sections of Geog 485 assignment code on the internet is a violation of academic integrity and may result in a penalty applied to your grade.

Class forums

Our course has discussion boards that you may use to consult your peers about any Python problem that you encounter. I encourage you to check them often and to participate by both asking and answering questions. I request that you make your questions focused and avoid pasting large blocks of code that would rob someone of the benefit of completing the assignment on their own. Short, focused blocks of code that solve a specific question are definitely okay. Code blocks that are not copied directly from your assignment are also okay.

I monitor all discussion boards closely; however sometimes I may not respond immediately because I want to give you a chance to help each other and work through problems together. If you post a question and wind up solving your own problem, please post the solution as a courtesy to other students who may have the same problem.

Consulting the instructor

I am available to help you at any point in the course and my goal is to respond to any personal message or e-mail within 24 hours on weekdays (notice the obvious problem if you have waited to begin your assignment until 24 hours before it's due!). I am happy to consult with you through e-mail, telephone, or whatever technology is necessary to help you be successful.

I ask that you try some of the many troubleshooting and help resources above before you contact me. If the issue is with your code and I cannot immediately see the problem, the resources we will use to find the answer will be the same that I listed above: the debugger, printing geoprocessing messages, looking for online code examples, etc. If you feel unsure about what you're doing, I'm available to talk through these approaches with you.