Switching one’s major (or subject altogether) is generally something that should not be done light-heartedly. But there are often valid reasons for doing so and it can take some time to notice these reasons.
Assuming you took some time to choose the subject you studied (which it sounds like you did) there are probably good reasons why you chose it. Probably you like maths (you hinted it be fun), maybe you were just good in maths at school or maybe you just wanted to be one of the cool nerds with glasses. One student at my university started studying chemistry because she found it fascinating and liked it at school. I started my master’s majoring in biochemistry because I liked the work we did in our practical courses and because it sounded interesting.
Once you’re now thinking about switching majors, something from your motivation must have changed. I’m inferring from what you said, that you spent more time (and maybe even had more fun) sitting at the PC doing some coding work. That’s a very positive way to think. The student I was talking about above underestimated the workload she was going to put into chemistry studies. She also failed a practical course (that really wasn’t dramatic; it’s a course that more than 10 % fail in their first attempt including me who’s doing a chemistry PhD now) and finally started spending more time with her other scholarly love, Japanese. In my case, I still (would) enjoy the practical parts but I underestimated the amount of rote memorisation required for passing the exams — I’m bad at that.
Once you’ve identified the true reason why you want to switch, you need to debate whether switching is an appropriate action or not. The student I keep mentioning switched to Japanese at a different university closer to her home. I still think that she just made herself too much work, tried to understand stuff way too deeply at a way too early level. She could have stuck with chemistry if she had tried to learn less (yes, that’s sometimes a thing). I haven’t spoken with her for quite a long time, but I assume she thinks it’s the right choice she made (She did take a long time considering it). In my case, switching majors from biochemistry to inorganic chemistry was essential to pass my master’s.
Now onto you. First off, programming or computer sciences are a lot closer to maths than Japanese is to chemistry (although they both sound similar to some, I am told). They’re not as close as inorganic and biochemistry in my opinion, though. It’s highly possible from my point of view to enter similar master’s programmes with both degrees, especially if you’re looking somewhere where both of them meet. You will also have gained valuable skills that you list in your question — problem-solving, critical thinking etc.
- Do you think that you can fulfill the requirements and achieve the degree your aiming for now?
- Do you think that your final mark might be (significantly?) worse if you switch?
- Are there computer science/programming programmes that allow a pure mathematician to start them?
If you answered those three and a half questions with yes then don’t switch. If you answered the half question with no and the others with yes, I would recommend you don’t switch. Only if you answer no to all three questions should you definitely switch.
The most important note of the whole text: Have a chat with an advisor if grains of doubt remain, e.g. if you’re not sure about fulfilling the requirements of whichever master’s programme you’re interested in due to your non-programming maths bachelor degree.