So, you want to multiply your sparse array by a not-sparse vector @p. Seems straightforward enough:

  my @r = (0) x scalar(@p) ;

  for my $i (0..$#row_index) {
    $r[$row_index[$i]-1] += $realval[$i] * $p[$col_index[$i]-1] ;
  } ;

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In reply to Re: Sparse Matrix Multiplication Problem by gone2015
in thread Sparse Matrix Multiplication Problem by neversaint

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