Back to square one I guess. This 

 sub popnum3 {
    my ( $x, $y, $z ) = @_;  # $_[3] is $zazb
    if ( $y == 0 ) {
        $aob[$x][0] = $initial * ( 1 + $z );
    }
    else {
        my @cPosns;
        push @cPosns, $-[0] while $_[3] =~ m{c}g;
        if (@cPosns) {
            my $offset = $cPosns[rand @cPosns];
            $aob[$x][$y] = $aob[$offset][ $y - 1 ] * ( 1 + $z );
        }
    }
    return $aob[$x][$y];
}

[download]
only seems to work relatively short strings, but not when the string gets much more than 500 characters. Then it throws 'uninitialized value in $offset' errors which I'm guessing means the algorithm didn't find the one 'c' that had to be there.

I admit I'm at my wit's end here. This looks like it should work, but it doesn't. There is a 'c' in every row, so that's not the problem.

THIS works 

sub popnum3 {
    my ( $x, $y, $z, $zazb ) = @_;
    if ( $y == 0 ) {
        $aob[$x][0] = $initial * ( 1 + $z );
    }
    else {
        while (1) {
            my $xda = int rand( $total + 1 );
            
            if ( substr( $zazb, $xda, 1 ) eq 'c' ) {
                $aob[$x][$y] = $aob[$xda][ $y - 1 ] * ( 1 + $z );
                last;
            }
        }
    }
    return $aob[$x][$y];
}

[download]
But takes about 5 seconds per row on the full array and since there's 8400 rows in the full run, that's about 12 hours.

Getting the run time down would be very helpful.

Thanks

In reply to Re^2: Yet more While issues by Dandello
in thread Yet more While issues by Dandello

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