Horner Rule Re: Converting an array of bytes into a BigInt

in reply to Converting an array of bytes into a BigInt - speed considerations

Horner rule for evaluating a polynomial from an array of coefficients:

sub bytearray_to_bigint {
    my $result = Math::BigInt->new('0');
    while (@_) {
        $result <<= 8; # was *= 256;
        $result += pop;
    }
    $result;
}
[download]

This algorithm is pretty efficient and needs no data tables kept.

After Compline,
Zaxo

Comment on Horner Rule Re: Converting an array of bytes into a BigInt Download Code

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Re: Horner Rule Re: Converting an array of bytes into a BigInt by BrowserUk (Patriarch) on Jan 24, 2003 at 06:58 UTC
Methinks maybe Horner used an 8-bit machine and binary rather than stringyfied numbers :^). Examine what is said, not who speaks. The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.	[reply]

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