NetLogo Debugging

Question

NetLogo being interactive makes debugging easy, but I yet to find any tools available for setting breakpoints and stepping through code. Please guide me if such exist. Or I can achieve the same with the current setup available.

Answer 1

I am not aware of such a tool if one exists. For debugging I use meaningful print statements. First I make a switch as a global parameter to set the debug mode on and off, then I add a statement to each method that prints which method updates which variable and in which order they were called (if debug mode is on).

I also use profiler extension which shows how many times each method was called and which one is the most or least time consuming one.

Answer 2

Not existing currently. Still, you can use one of the alternatives from above or you might take a look at user-message (https://ccl.northwestern.edu/netlogo/docs/dictionary.html#user-message), which will pop up a dialog. This will also block the execution at that step, although not providing you with a jump-to-next-line mechanism, for me this solution proved to be the best.

Answer 3

Another possibility is to do the debugging in any modern browser if/when NetLogo Web produces source maps. This way one can set breakpoints in the NetLogo code and use Chrome or FireFox or IE11's developer tools on the NetLogo code.

Answer 4

I have used user-message and inspect together as the debugging tool for NetLogo. Here is a video demo on how to use them to identify the cause of an error.

• the reason for using inspect is to examine all properties of an object when we are not sure where exactly went wrong
• using user-message to print out some instruction, output some outcome and halt the program