I need to fit as much information as I can into a small file size. In this case, the data is in a comma separated format and all values are stored as 2dp decimals (no titles).
I've had a look and my understanding is that all the characters I need are stored using ASCII (1 byte per character) in my standard .txt file that I am currently using. Apparently ASCII has 256 possible values, which is way more than I need - I could get by with only 16 characters.
Could I save my data in some kind of 4bit text file? I will be creating the file using c# (all google searches result in advice on making a text file, not how to make a smaller "font" text). Would doing this save any space in the end anyway? I could zip up anything before I send it, but any advice on ideas to get the filesize down would be greatly appreciated.
I think that the question is legitimate, but the answer is that you impose logical conditions that leave no place for any solution.
So if you could avoid CSV structure for your custom structure you could save something, but you need it and it pretty much determines your solution. The only variable left is how do you encode the text, but you can't encode the text in less than 8 bits, you can just use higher values like Unicode (16 bits).
I won't comment on using compression as you already mentioned that you are looking for alternative answers and you are aware of that.