Define additional math operators to be typeset in roman
It may be a very simple question to people who know.
If I want to type commonly used functions like exponential function exp(x) or sinusoidal function sin(x), I use
\sin(x) in LaTeX and the results looks nice (fonts become different from other non-function characters). However, when I type error function
\erf(x), it gives me error messages. If I remove
\, it compiles fine but the "erf(x)" fonts just look the same to other non-function characters. Could anyone please tell me how to make the error function fonts look like as exponential function in a math environment? Thanks very much.