Convert numbers to SI prefix

Question

Is there a R function (or any package) allowing to format numbers (integer) using standard unit prefix (Kilo, Mega etc ...), so

10 -> 10
100 -> 1K
0.01         


        

Answer 1

I was looking for Thousand(K), million(M) and Billion(B) number converter. I modified this routine to take a numeric vector/single number spitting out the required output.

CurrencyFormat <-function (number,rounding=F) 
{
    first <- TRUE
    lut <- c( 1, 1000, 1000000, 1000000000,1000000000000 )
    pre <- c("", "K", "M", "B", "T")
    if (length(number) > 1) {
        for (cnt in 1:length(number)){        
            ix <- findInterval(number[cnt], lut)
            if (ix != 0 | ix != 1){
                if (rounding==T) {
                    sistring <- paste(round(number[cnt]/lut[ix]), pre[ix])
                }
                else {
                    sistring <- paste(signif(number[cnt]/lut[ix],digits=5), pre[ix])
                }
                if (first){
                    tnumber <- sistring
                    fnumber <- tnumber
                    first <- FALSE
                }
                else
                    fnumber <- append(fnumber, sistring)
            }
            else {
                sistring <- number[cnt]
                if (first){
                    tnumber <- sistring
                    fnumber <- tnumber
                    first <- FALSE
                }
                else
                    fnumber <- append(fnumber, sistring)
            }
        }
        return(fnumber)
    }
    else{
        ix <- findInterval(number, lut)
        if (ix != 0 | ix != 1){
            if (rounding==T) {
                sistring <- paste(round(number/lut[ix]), pre[ix])
            }
            else {
                sistring <- paste(signif(number/lut[ix],digits=5), pre[ix])
            }
            return(sistring)
        }    
        else
            return(number)
    }
}

Examples:

CurrencyFormat(1.25,F)
[1] "1.25 "

CurrencyFormat(1000.25,F)
[1] "1.0002 K"

CurrencyFormat(c( 1,45,1234, 4.36e+06, 2.84e+04, 2.01e+06),F)
[1] "1 "      "45 "     "1.234 K" "4.36 M"  "28.4 K"  "2.01 M"