I’m working on the handwritten kanji character recognition. At least that part doesn’t need reworking, I thought. Maybe it doesn’t, though I plan to improve on it a bit. What gives me headaches (apart from the fast changing weather) is that I don’t really understand a lot of the code now.
As I’m working on the new version, I try to describe what each part of the code does, so I’m adding comments everywhere. In the original code there was almost none. I could easily understand what the program does, so why add any? Good code explains itself? I have seen that line a lot before. Unfortunately it’s only true about code which solves a very simple, easy to understand problem with a simple algorithm. NOT for handwritten kanji character recognition.
I can’t make much out of the old code without considerable effort doing so. Because of this, even copying the old code takes a lot of time. Not that I’m just copying it either. I’m not sure whether all of my old decisions made sense or not, but regardless of that I would probably make different ones now. It’d be good if someone reading that code (even if it’s me years from now) could figure out why those decisions were made.
I think I’ve learned my lesson, but that doesn’t mean every single line will get commented either. Some parts really do explain themselves. Others might not be obvious to everyone, but as I was solving the same problems the same way years back, they will be easy to read in the future too. I have seen code before which had more comments than code, and it was hard to read because of that. If the algorithm is complicated, explaining it in a few long paragraphs at the start of the code is better than writing a description about each line.
Just to clarify, I’m writing this because it helps me concentrate while I code. I doubt anyone will change their habits because of this blog.
zkanji 
Necessity of writing comments in code
I’m working on the handwritten kanji character recognition. At least that part doesn’t need reworking, I thought. Maybe it doesn’t, though I plan to improve on it a bit. What gives me headaches (apart from the fast changing weather) is that I don’t really understand a lot of the code now.
As I’m working on the new version, I try to describe what each part of the code does, so I’m adding comments everywhere. In the original code there was almost none. I could easily understand what the program does, so why add any? Good code explains itself? I have seen that line a lot before. Unfortunately it’s only true about code which solves a very simple, easy to understand problem with a simple algorithm. NOT for handwritten kanji character recognition.
I can’t make much out of the old code without considerable effort doing so. Because of this, even copying the old code takes a lot of time. Not that I’m just copying it either. I’m not sure whether all of my old decisions made sense or not, but regardless of that I would probably make different ones now. It’d be good if someone reading that code (even if it’s me years from now) could figure out why those decisions were made.
I think I’ve learned my lesson, but that doesn’t mean every single line will get commented either. Some parts really do explain themselves. Others might not be obvious to everyone, but as I was solving the same problems the same way years back, they will be easy to read in the future too. I have seen code before which had more comments than code, and it was hard to read because of that. If the algorithm is complicated, explaining it in a few long paragraphs at the start of the code is better than writing a description about each line.
Just to clarify, I’m writing this because it helps me concentrate while I code. I doubt anyone will change their habits because of this blog.