Hi, I was using Acme::AsciiArt2HtmlTable which makes tables with coloured cells but has some problems such as limited colours and it's a bit slow(I guess because it's in Acme namespace it's not really supposed to be used for serious stuff). anyway got your colourramp1785 and modified it a bit to work with almut's GD snippet: 
my @map=(
    sub{(         0,             0,   $_[0] * 255 )},
    sub{(         0,     $_[0]*255,           255 )},
    sub{(         0,           255, (1-$_[0])*255 )},
    sub{( $_[0]*255,           255,             0 )},
    sub{(       255, (1-$_[0])*255,             0 )},
    sub{(       255,             0,     $_[0]*255 )},
    sub{(       255,     $_[0]*255,           255 )},
);
 
sub ramp {
    my( $v, $vmin, $vmax ) = @_;
 
    ## Peg $v to $vmax if it is greater than $vmax
    $v = $vmax if $v > $vmax;
    ## Or peg $v to $vmin if it is less tahn $vmin.
    $v = $vmin if $v < $vmin;
    ## Normalise $v relative to $vmax - $vmin
    $v = 
    ( $v    - $vmin ) /
    ( $vmax - $vmin ) ;
    ## Scale it to the range 0 .. 1784
    $v *= 1785;
 
    my @a = 
    map { int } 
    $map[$v/255]->( ($v % 255) / 256 );
 
    #print join(',',@a)."\n";
 
    return 
    ($a[2]<<8 ) |
    ($a[1]<<4 ) |
    ($a[0]    ) ;
};

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I'm using it in a loop like so: $img->setPixel($x, $y, $some_val_from_a_table ,  1,16 )) ; it works ok but sometime produces colours which are too near to each other to be distinguished easily. Browser_Uk , how di dyou write your colour ramp ? I read about some colour ramps <-- here, but not sure if they fit the common usage.

In reply to Re^4: visualizing data in a table by spx2
in thread visualizing data in a table by punkish

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