##! perl -slw
use strict;

sub genScaler {
    my( $minout, $maxout, $minin, $maxin ) = @_;
    my $outRange = $maxout - $minout;
    my $inRange = $maxin - $minin;
    my $factor = $inRange / $outRange;
    sub {
        my $in = shift;
        return $minout + ( $in / $factor );
    }
}

sub genLogScaler {
    my( $minout, $maxout, $minin, $maxin ) = @_;
    sub {
        my $in = shift;
        $in = 1 if $in < 1;
        return $minout + log( $in );
    }
}

my $fscale = genScaler( 1, 10, 0.1, 8000 );

print "Linear:";
printf "%7.1f -> %.1f\n", $_, $fscale->( $_ ) for 0.1, 1, 10, 100, 800, 1000, 4000, 6000, 8000;

print "\nLog:";
my $lscale = genLogScaler( 1, 10, 0.1, 8000 );

printf "%7.1f -> %.1f\n", $_, $lscale->( $_ ) for 0.1, 1, 10, 100, 800, 1000, 4000, 6000, 8000;