What is the opposite function of max.col (R language)

Question

What is the opposite function of max.col (R language).

I couldn't find min.col or relevant info in the manual:

https://stat.ethz.ch/R-manual/R-devel/library/base/html/maxCol.html

I'm trying to generate an opposite function of this:

cols = which(names(df) %in% c( "avp", "USD.KRW","cd")); 
df$max_col = names(df)[cols][max.col(df[cols])]

Answer 1

You can use

min.col <- function(m, ...) max.col(-m, ...)

Used in formal optimization (where many tools prefer to find a minimum of a function), the opposite of a maximal number is the minimal negative number.