I am trying to extract the number from a string such as : keff = 1.23456 with an estimated standard deviation of 0.12345. I am interested in extracting both numbers, which will change with the data file. I tried to do this with a test program first to see how it works: 

$out_file = out1;
open (OUT. "$out_file");
  while (OUT) {
   if (/Time: (..):(..):(..)/) {
       $hours = $1;
       $mins  = $2;
       $secs  = $3;
     }
  }
close (OUT);
print "hours =: $hours";

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The out file contains a single line: Time: 04:18:02 I get an error message stating: Use of unintialized value in pattern match (m//) at test.pl line 8. What am I doing wrong? If I can get this case to work, maybe I can get the first and more complicated case working. Thanks, Bruce

In reply to extracting number from middle of string by Anonymous Monk

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