R Newbie - Histograms/Frequency of values incorporating a quantity Column [duplicate]

Answer 1

Use dat$V3 to indicate how often you need each row of dat, by feeding it into the times parameter of rep():

>  dat <- read.table(text='45.3, 17, 3 
  + 48, 19, 2',sep=',')
> dat[rep(1:nrow(dat),times=dat$V3),]
      V1 V2 V3
1   45.3 17  3
1.1 45.3 17  3
1.2 45.3 17  3
2   48.0 19  2
2.1 48.0 19  2