i haven't been doing any numerical computing for the last 5 or so years, but previously I was using python's numpy + scipy pretty heavily for data-science / app

i haven't been doing any numerical computing for the last 5 or so years, but previously I was using python's numpy + scipy pretty heavily for data-science / applied-maths stuff, and under the hood quite a lot of the numerical optimisation algorithms in scipy are wrappers around old fortran libraries. so at that stage it still gets used but perhaps most people can pretend it doesnt exist. similarly, the backend of the original "random forest" machine learning algorithm for R was written in fortran, and then wrapped as an R library, but as an R user you could largely pretend that fortran didnt exist. R was a pitifully slow language so this was a good move.