Hi Monks, I'm new to Perl/Tk but already ran into a strange problem. I made a program (source included) that accepts numbers with the entry widget. As long as i use integers, the program acts as expected, but when i use decimals, it gets weird. When the program is not stopped, and another calculation is made (with a decimal under 1 ie. 0.05) the calculation is performed correct, but re-running the program w/o a change, any change to the field with the decimal, results in an error message at the console. When the decimal is above 1 (ie. 1.5) the error message will not appear, but the calculated value changes. So i wonder if somehow, "entry" has a problem with retaining the value of decimals.

Error message:

Tk::Error: Illegal division by zero at C:\perl\dwnspd.pl line 79.
 main::__ANON__ at C:\perl\dwnspd.pl line 79
 Tk callback for .button
 Tk::__ANON__ at C:/Strawberry/perl/site/lib/Tk.pm line 251
 Tk::Button::butUp at C:/Strawberry/perl/site/lib/Tk/Button.pm line 17
+5
 <ButtonRelease-1>
 (command bound to event)

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use strict;
use warnings;
use 5.010;
use Tk;
#use Win32::Console;
#Win32::Console::Free();
system("cls");

# declarations
my $netspdx=1;
my $netspdy=0;
my $netuse=0.05;
my $fsizex=3;
my $fsizey=0;
my $mw;
my $breed=400;
my $hoog=200;
my $cent=$breed/2;  # needs -anchor=>'center'
my $tekst;
my $button;
my $but1;
my $but2;
my $but3;
my $but4;
my $but5;
my $but6;
my $entry1;
my $entry2;
my $entry3;
my $col0=40;        # need -anchor=>'w'
my $col1=$cent-35;  # need -anchor=>'w' 
my $col2=$cent+30;  # need -anchor=>'w'
my $col3=$breed-40; # need -anchor=>'w'
my $row0=20;
my $row1=40;
my $row2=60;
my $row3=80;
my $row4=90;
my $row5=110;  


    initi();
    $tekst=$mw  -> Label(-text=>"Fill in the fields and check the righ
+t boxes") -> place(-x=>$cent, -y=>$row0, -anchor=>'center');
    
    $tekst=$mw  -> Label(-text=>"Network speed")                      
+                  -> place(-x=>$col0, -y=>$row1, -anchor=>'w');
    $entry1=$mw -> Entry(-justify=>'right',-textvariable=> \$netspdx, 
+-width=>5)        -> place(-x=>$cent, -y=>$row1, -anchor=>'center');
    
    $but1=$mw   -> Radiobutton(-text => 'Gb', -variable=>\$netspdy, -v
+alue=>1000000000) -> place(-x=>$col2,     -y=>$row1, -anchor=>'w');
    $but1->select();
    $but2=$mw   -> Radiobutton(-text => 'Mb', -variable=>\$netspdy, -v
+alue=>1000000)    -> place(-x=>$col2+50,  -y=>$row1, -anchor=>'w');
    $but3=$mw   -> Radiobutton(-text => 'Kb', -variable=>\$netspdy, -v
+alue=>1000)       -> place(-x=>$col2+100, -y=>$row1, -anchor=>'w');
        
    $tekst=$mw  -> Label(-text=>"Avg network use in %")               
+                  -> place(-x=>$col0, -y=>$row2, -anchor=>'w');
    $entry2=$mw -> Entry(-justify=>'right',-textvariable=> \$netuse,-w
+idth=>5)          -> place(-x=>$cent, -y=>$row2, -anchor=>'center');
    
    $tekst=$mw  -> Label(-text=>"File size")                          
+                  -> place(-x=>$col0, -y=>$row3, -anchor=>'w');
    $entry3=$mw -> Entry(-justify=>'right',-textvariable=> \$fsizex,-w
+idth=>5)          -> place(-x=>$cent, -y=>$row3, -anchor=>'center');
    $but4=$mw   -> Radiobutton(-text => 'GB', -variable=>\$fsizey, -va
+lue=>1000000000)  -> place(-x=>$col2,     -y=>$row3, -anchor=>'w');
    $but4->select();
    $but5=$mw   -> Radiobutton(-text => 'MB', -variable=>\$fsizey, -va
+lue=>1000000)     -> place(-x=>$col2+50,  -y=>$row3, -anchor=>'w');
    $but6=$mw   -> Radiobutton(-text => 'KB', -variable=>\$fsizey, -va
+lue=>1000)        -> place(-x=>$col2+100, -y=>$row3, -anchor=>'w');
    
    $tekst= $mw -> Label(-text=>"Estimated time") -> place(-x=>$col0, 
+-y=>$row5, -anchor=>'w');
    $tekst= $mw -> Label(-text=>"minutes") -> place(-x=>$col2, -y=>$ro
+w5, -anchor=>'w');
    endi();
    

# subroutines
    # init info
sub initi{
$mw = new MainWindow(-height=>$hoog,-width=>$breed,-title=>'Downloadti
+me estimator'); 
$mw -> geometry("+100+100");
}

    # end info
sub endi {
    $button = $mw -> Button(-text => "Okay", -command => sub {        
+                                        
        $tekst= $mw -> Label(-text=>"                   ") -> place(-x
+=>$cent, -y=>$row5, -anchor=>'center'); # not very elegant, any ideas
+ ?
        $tekst= $mw -> Label(-text=> int(
            (($fsizex*$fsizey)  /  ((($netspdx*$netspdy)/100)  *$netus
+e))  /60
        ) )-> place(-x=>$cent, -y=>$row5, -anchor=>'center');
    }) -> place(-x=>$col0, -y=>$hoog-50, -anchor=>'w');
    
    $button = $mw -> Button(-text => " Exit ", -command => sub { exit 
+}) -> place(-x=>$col3, -y=>$hoog-50, -anchor=>'e');
MainLoop;
}

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In reply to Tk : Entry widget-Strange behaviour with decimals by Caerwyn1955

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