my $f = unpack('N', pack('B32', "01000010001111000000000000000000")) ; printf "0x%08X = %12.9f\n", $f, conv_HFP($f) ; sub conv_HFP { my ($f) = @_ ; my $s = ($f & 0x8000_0000) ? -1 : +1 ; my $e = (((($f >> 24) & 0x7F) - 0x40) * 4) - 24 ; return $s * ($f & 0xFF_FFFF) * (2 ** $e) ; } ; #### my $f = unpack('N', pack('B32', "01000010001111000000000000000000")) ; printf "0x%08X = %12.9f\n", $f, conv_BFP($f) ; sub conv_BFP { my ($f) = @_ ; my $s = ($f & 0x8000_0000) ? -1 : +1 ; my $e = ((($f >> 23) & 0xFF) - 0x7F) - 23 ; return $s * (($f & 0x7F_FFFF) | 0x80_0000) * (2 ** $e) ; } ;