Solved

Perl code to read from a file

Posted on 2009-07-06
7
159 Views
Last Modified: 2012-05-07
Hello, I have a small stats project to work on.

I am learning perl, but have to learn it in a very short space of time.

Could anyone help me with some code, which would open a text file, draw out 7 comma delineated numbers, ie, 34,56,76,12,1,69,64 and insert them as individual entities into scalar variables ?

thanks

Mick
0
Comment
Question by:Europa MacDonald
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 3
7 Comments
 
LVL 40

Accepted Solution

by:
mrjoltcola earned 500 total points
ID: 24789471
Here is one way.
#!/usr/bin/perl
 
open(IN, "<test.txt") or die;
 
my $s;
 
while($s = <IN>) {
   if($s =~ /(\d+),(\d+),(\d+),(\d+),(\d+),(\d+),(\d+)/) {
      my ($n1, $n2, $n3, $n4, $n5, $n6, $n7) = ($1, $2, $3, $4, $5, $6, $7);
      print "n1 = $n1,  n7 = $n7\n";
   }
}

Open in new window

0
 

Author Closing Comment

by:Europa MacDonald
ID: 31600371
thankyou
0
 

Author Comment

by:Europa MacDonald
ID: 24789497
it doesn't print to the command line screen, should it ?
0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 40

Expert Comment

by:mrjoltcola
ID: 24789514
You are welcome.

Also look at the "split" function, you can split comma separated lines easily with it. I often prefer an explicit regular expression,


my @nums = split /,/, "1,2,3,4,5,6,7"

#!/usr/bin/perl
 
open(IN, "<test.txt") or die;
 
my $s;
 
while($s = <IN>) {
   my @nums = split /,/, $s;
   foreach (@nums) {
      print "$_\n";
   }
}

Open in new window

0
 
LVL 40

Expert Comment

by:mrjoltcola
ID: 24789520
>>it doesn't print to the command line screen, should it ?

Yes, with the test data I used. I made a file test.txt with one line of text:  34,56,76,12,1,69,64

0
 

Author Comment

by:Europa MacDonald
ID: 24789523
I am using windows, should this make a difference ?
0
 

Author Comment

by:Europa MacDonald
ID: 24789532
I apologise, it did that time.
0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Did you know SD-WANs can improve network connectivity? Check out this webinar to learn how an SD-WAN simplified, one-click tool can help you migrate and manage data in the cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

On Microsoft Windows, if  when you click or type the name of a .pl file, you get an error "is not recognized as an internal or external command, operable program or batch file", then this means you do not have the .pl file extension associated with …
A year or so back I was asked to have a play with MongoDB; within half an hour I had downloaded (http://www.mongodb.org/downloads),  installed and started the daemon, and had a console window open. After an hour or two of playing at the command …
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
Six Sigma Control Plans

636 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question