How can i rescale every column in my data frame to a 0-100 scale? (in r)

Question

i am trying to get all the colums of my data frame to be in the same scale..

right now i have something like this... where a is on a 0-1 scale b is on a 100 scale and

Answer 1

My experience is that this is still unanswered, what if one of the columns had a -2, the current answer would not produce a 0-100 scale. While I appreciate the answer, when I attempted it, I have variables that are -100 to 100 and this left some negative still?

I have a solution in case this applies to you:

rescale <- function(x) (x-min(x))/(max(x) - min(x)) * 100
dat <- rescale(dat)