I am a Data Scientist, software developer and researcher (PhD) and I have an interest in (among others) Artificial Intelligence, Optimization, Robotics, Machine learning, and programming (C++, Python and Java).
Programmers know that any modification of the source code has a danger of introducing errors, so it is a good rule to change as little as possible in a program that works.
H.P. Langtangen, A Primer on Scientific Programming with Python. Texts in Computational Science and Engineering 6, ©Springer-Verlag Berlin Heidelberg 2012 137