Coding Tips

Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live. John Woods

A few tips for writing code, especially that kind doing computationally costly simulations.

None of these points is obligatory, neither is the list comprehensive. But bear in mind that its the result of personal (practical) experience (of several people) over quite some time.

Coding conventions

  • Use meaningful filenames.
    • Develop a sensible directory hierarchy for your codes and projects.
    • Where possible, write reusable code and store it in a separate directory that gets added to the Matlab path.
  • Use functions rather than scripts, whereever possible.
  • Try to avoid for loops whereever possible.
    • Matlab offers you a broad range of matrix manipulation methods that are much faster in Matlab than for loops.
  • Document your code carefully.
    • Note: Even you will struggle to understand what your code does, if you look at it after two months.
    • Possibly, others want to make use of your code, at least try to understand what you did, and if necessary, adapt it for their needs.
  • Add a description of what the file does at the top of all your files.
    • Add references to papers if relevant.
  • Add a history bit at the top of all your files (below the general description).
    • At least, the date of the last modification.
    • If you modify something, add a short note what has changed (and why).
  • Use sensible names for variables.
    • It doesn't matter if they are long.
    • Where applicable, add comment lines telling what these variables are.
  • Add comment lines in the source code describing shortly what the following lines do.

If you plan to add your code or at least parts of it to a thesis:

  • Beware of the line lenghts
    • Display a vertical line for the maximum line length in your editor1)
    • Break long lines using


  • Save results to a file.
    • Easiest: Save as Matlab file (“.mat”).
    • Use a proper name that allows you to easily recognise the file contents.
    • Save all the parameters you used for the calculations, and that are important to repeat it.
    • Perhaps also save a string with a description in it.
  • Save the graphics files.
    • Save as Matlab fig file (allows later modifications)
    • Save as EPS or PDF file (allows including in reports)
      • (Normally) a vector format, therefore allows scaling
  • Write short summaries.
    • Whereever possible and suitable, sum up your results for a (sub-)project before moving on to the next problem.
The Matlab editor offers this possibility.
en/software/matlab/tips/index.txt · Last modified: 2017/12/09 20:09 (external edit)