A lot of funds use MATLAB whereas a large group of funds are R based. Some big ones like AQR have started to make heavy use of Python for creation of research infrastructure and strategy development. I am creating this thread to hear from the ET residents active in quantitative trading - which of these tools is your choice and why? If you use multiple tools (among R, MATLAB and Python), all the more power to you! It will be very interesting to have a debate on which tool you find most appropriate for what kind of tasks and why. Specifically, lets discuss: Relative advantages/disadvantages of these 3 languages to develop research infrastructure and strategy development. Following the philosophy of Ray Dalio, lets have an open, argumentative, passionate "no holds barred" kind of debate and lets uncover the truth!