dgemm.R

#!/usr/bin/Rscript

argv <- commandArgs(trailingOnly = TRUE)

nfrom = 128
nto = 2048
nstep = 128
loops = 1

if ( length(argv) > 0 ) {

  for ( z in 1:length(argv) ) {

    if ( z == 1 ) {
      nfrom <- as.numeric(argv[z])
    } else if ( z==2 ) {
      nto <- as.numeric(argv[z])
    } else if ( z==3 ) {
      nstep <- as.numeric(argv[z])
    } else if ( z==4 ) {
      loops <- as.numeric(argv[z])
    }
  }

}

p=Sys.getenv("OPENBLAS_LOOPS")
if ( p != "" ) {
  loops <- as.numeric(p)
}	


cat(sprintf("From %.0f To %.0f Step=%.0f Loops=%.0f\n",nfrom, nto, nstep, loops))
cat(sprintf("      SIZE             Flops                   Time\n"))

n = nfrom
while ( n <= nto ) {

  A <- matrix(runif(n*n), ncol = n, nrow = n, byrow = TRUE)
  B <- matrix(runif(n*n), ncol = n, nrow = n, byrow = TRUE)

  l = 1

  start <- proc.time()[3]

  while ( l <= loops ) {

    C <- A %*% B
    l = l + 1
  }

  end <- proc.time()[3]
  timeg = end - start
  mflops = ( 2.0 *n*n*n ) * loops / ( timeg * 1.0e6 )

  st = sprintf("%.0fx%.0f :",n , n)
  cat(sprintf("%20s %10.2f MFlops %10.6f sec\n", st, mflops, timeg))

  n = n + nstep

}