Take a look at my demo code... The key lines for 5 columns are: 
-cols => 5,                             #################
-colwidth=> -( ($pix_width-30)/5),      #################  
                                        # note: not -colWidth

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If the -colwidth is negative, it is in pixels. I subtracted a "fudge factor" to allow for the scrollbars. Change 5 in both places to be whatever you want and you will get that many evenly spaced columns. 
#!/usr/bin/perl -w
use strict;

use Tk;
use Tk::TableMatrix;

my $mw = MainWindow->new;
$mw->configure(-title=> "Some Title");
my $pix_height  = $mw->screenheight;
my $pix_width   = $mw->screenwidth;
my $color_depth = $mw->screendepth;

$mw->geometry("$pix_width"."x400+0+0"); ###########
                               
my $table_frame = $mw->Frame(-height=>'10',-width=>'30',
                       -relief=>'groove',-borderwidth=>'3'
                       )->pack(-expand=>1, -fill=>'both',-pady=>'0');

my %tMainHash;
 
my $table = $table_frame->Scrolled('TableMatrix',
 -cols => 5,                             #################
 -colwidth=> -( ($pix_width-30)/5),      #################
 -rows =>16,  
 -variable => \%tMainHash,
 -state => 'disabled',   # no direct editing of cells
 -resizeborders => 'col', 
 -bg => 'white',
 -rowheight => 1,  #make row display more compact....
 -bd => [0,1,0,1],
 -justify => 'left',
 -drawmode => 'compatible',
 -wrap => 0,
 -relief => 'solid',
 -scrollbars=>'se',
 -exportselection =>0,
)->pack(-expand =>1, -fill=>'both');
$table->rowHeight(0,2);  #varies height of title row (0)
$table->tagRow('title',0);
$table->tagConfigure('title', -bd=>2, -relief=>'raised');

MainLoop;

[download]

In reply to Re: proportional resizing tk table by Marshall
in thread proportional resizing tk table by welle

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