subroutine..help

dee00zee has asked for the wisdom of the Perl Monks concerning the following question:

I try to use subroutine in my program but it
didn't return the value that I want.What is wrong
with my code?

example:

sub coor        
{
    my ($a,$b);    
        
    $f=$a+109;
    $g=$b+5;
    
    @in=($f,$g);    
}    

######################################################
#MAIN PROGRAM        
            
&coor("1","2");
@y1_opp=&coor;
print "@y1_opp\n";
[download]

The output I get is $f=109 and $g=5
My subroutine did not work :(

Janitored by Arunbear - added code tags, as per Monastery guidelines

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Re: subroutine..help by Zaxo (Archbishop) on Oct 29, 2004 at 05:59 UTC
You're not making any use of the arguments in your subroutine, so $a, $b are both zero. You shouldn't rely on global variables to convey information in and out of a subroutine. Here is how your code might be better written, `sub coor { my ($c, $d) = @_; return ( $c + 109, $d + 5 ); } my @y1_opp = coor( 1, 5); print "@y1_opp\n";` [download] I've renamed $a and $b since they are sacred to sort in Perl. After Compline, Zaxo	[reply] [d/l]
Re^2: subroutine..help by hmerrill (Friar) on Oct 29, 2004 at 12:01 UTC
Just personal preference here, but I prefer to use "shift" instead of picking off arguments from @_, like this: `sub coor { my $c = shift; # get 1st argument my $d = shift; # get 2nd argument return ( $c + 109, $d + 5 ); }` [download] And, the OP should use "use strict;" and either "-w" on the first perl line or "use warnings;".	[reply] [d/l]
Re: subroutine..help by TedPride (Priest) on Oct 29, 2004 at 09:37 UTC
`use strict; use warnings; my @y1_opp = &coor(1,2); print "@y1_opp\n"; sub coor { return ($_[0]+109, $_[1]+5); }` [download]	[reply] [d/l]
Re: subroutine..help by gube (Parson) on Oct 29, 2004 at 14:36 UTC
If u wish please, try this code `sub coor { my ($a,$b)=@_; $f=$a+109; $g=$b+5; return($f,$g); } @y1_opp=&coor("1","2"); print "@y1_opp\n";` [download]	[reply] [d/l]
Re: subroutine..help by artist (Parson) on Oct 29, 2004 at 15:14 UTC
You have already got the answer: You should have thought: How you are getting the values inside the subroutine which is passed to the subroutine. What you have :my($a,$b); What you Should have: my($a,$b) = @_;	[reply]