For math, underscores evoke the "_ is subscript" convention of TeX. That can be a good thing, e.g. err_total = err_intrinsic + err_extrinsic which might mi

For math, underscores evoke the "_ is subscript" convention of TeX. That can be a good thing, e.g. err_total = err_intrinsic + err_extrinsic which might mirror the notation in a paper that the code implements.