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From: wolf on 3 Aug 2010 09:10
Thomas Andersson schrieb:
> As the topic says. I ahve a settings file where each line contains 2 numbers
> of varying length and I want to extract each number and assign to a
> variable, how would I go about that?
>
>
use SPLIT: split( /\s+/, $input) splits on any whitespace(s) including
tab(s). split( /\t/, $input) splits on every tab.

open (my $infile, '<', 'mynumbers.txt') or die;
my ($input, $number1, $number2);

while ($input = <$infile>) {
chomp $input;
($number1, $number2) = split( /\s+/, $input);
print $number1,'--',$number2,"\n";
}
close $infile;
From: J. Gleixner on 3 Aug 2010 10:49
wolf wrote:
> Thomas Andersson schrieb:
>> As the topic says. I ahve a settings file where each line contains 2
>> numbers of varying length and I want to extract each number and assign
>> to a variable, how would I go about that?
>>
> use SPLIT: split( /\s+/, $input) splits on any whitespace(s) including
> tab(s). split( /\t/, $input) splits on every tab.
>
> open (my $infile, '<', 'mynumbers.txt') or die;
Always include the error message:

or die $!;

Better would be to include the file name and more helpful details:

or die "Can't open mynumbers.txt for read: $!";

> my ($input, $number1, $number2);
Declare the variables in the smallest scope.

>
> while ($input = <$infile>) {
while( my $input = <$infile> ) {
> chomp $input;
> ($number1, $number2) = split( /\s+/, $input);
my ( $number1, $number2) = split( /\s+/, $input);
> print $number1,'--',$number2,"\n";
> }
> close $infile;
From: sln on 3 Aug 2010 11:32
On Tue, 03 Aug 2010 15:10:47 +0200, wolf <wolf(a)gsheep.com> wrote:

>Thomas Andersson schrieb:
>> As the topic says. I ahve a settings file where each line contains 2 numbers
>> of varying length and I want to extract each number and assign to a
>> variable, how would I go about that?
>>
>>
>use SPLIT: split( /\s+/, $input) splits on any whitespace(s) including
>tab(s). split( /\t/, $input) splits on every tab.
>
>open (my $infile, '<', 'mynumbers.txt') or die;
>my ($input, $number1, $number2);
>
>while ($input = <$infile>) {
> chomp $input;
> ($number1, $number2) = split( /\s+/, $input);

Don't forget to validate $number(s) or you could run
into errors when doing stuff like
if $number1 == $number2

So after the split() it could be validated something like
$number1 =~ s/^\s+//;
$number1 =~ s/\s+$//;
if $number1 =~ /^[+-]?\d*?\.?\d+$/ # for non-exponent

Or it can all be done in one line
($number1, $number2) = $input =~ /\s*([+-]?\d*?\.?\d+)\s+([+-]?\d*?\.?\d+)/;

-sln
From: Thomas Andersson on 3 Aug 2010 22:50
Justin C wrote:
> On 2010-08-03, Thomas Andersson <thomas(a)tifozi.net> wrote:
>> As the topic says. I ahve a settings file where each line contains 2
>> numbers of varying length and I want to extract each number and
>> assign to a variable, how would I go about that?
>
> TMTOWTDI, here's one, it may not be a good one.

> How long are you numbers? Are they formatted?

2 variable length numbers that are tab delimiterd, someone suggest the split
function which worked perfect.

my ($cpid, $lproc) = split (/\t/, $pidlist);


From: wolf on 4 Aug 2010 06:44
sln(a)netherlands.com schrieb:
> On Tue, 03 Aug 2010 15:10:47 +0200, wolf <wolf(a)gsheep.com> wrote:
>
>> Thomas Andersson schrieb:
>>> As the topic says. I ahve a settings file where each line contains 2 numbers
>>> of varying length and I want to extract each number and assign to a
>>> variable, how would I go about that?
>>>
>>>
>> use SPLIT: split( /\s+/, $input) splits on any whitespace(s) including
>> tab(s). split( /\t/, $input) splits on every tab.
>>
>> open (my $infile, '<', 'mynumbers.txt') or die;
>> my ($input, $number1, $number2);
>>
>> while ($input = <$infile>) {
>> chomp $input;
>> ($number1, $number2) = split( /\s+/, $input);
>
> Don't forget to validate $number(s) or you could run
> into errors when doing stuff like
> if $number1 == $number2
>
> So after the split() it could be validated something like
> $number1 =~ s/^\s+//;
> $number1 =~ s/\s+$//;
> if $number1 =~ /^[+-]?\d*?\.?\d+$/ # for non-exponent
>
> Or it can all be done in one line
> ($number1, $number2) = $input =~ /\s*([+-]?\d*?\.?\d+)\s+([+-]?\d*?\.?\d+)/;
>
> -sln

Dear gents,

these are all valid arguments to improving the code :)

However, since the original poster didn't even know how to wield SPLIT,
i wanted to keep it as simple and un-confusing as possible,
demonstrating just SPLIT as the important thing to handle.
As such the code works well enough :p

Cheers, wolf
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