Dear Monks,

This is the first time I am asking a question! I am trying to read a block of data (by matching a string) from one file and paste it in another file, at a specific line number. I have used the Tie::File option for the second file. My data in the first file (input file), is as follows:

 NODE              32        0.00000        0.00000       -1.90000
 NODE              33        0.00000        0.00000       -5.50000
 NODE              34        0.00000        0.00000       -9.00000
 NODE              35        0.00000        0.00000      -15.00000
 NODE              36        0.00000        0.00000      -18.90000
 NODE              37        0.00000        0.00000      -22.40000
 NODE              38        0.00000        0.00000      -25.90000
 NODE              39        0.00000        0.00000      -29.00000
 NODE              40        0.00000        0.00000      -32.50000
 NODE              41        0.00000        0.00000      -33.90000
 NODE              42        0.00000        0.00000      -62.90000
 BEAM              26        27       26        1       14       1
 BEAM              27        28       27        1       13       1
 BEAM              28        29       28        1       12       1
 BEAM              29        30       29        1       11       1
 BEAM              30        31       30        1       10       1
 BEAM              31        32       31        1        9       1
 BEAM              32        33       32        1        8       1
 BEAM              33        34       33        1        7       1
 BEAM              34        35       34        1        6       1
 BEAM              35        36       35        1        5       1
 BEAM              36        37       36        1        4       1

[download]

And the code I have written, is this:

use Tie::File;
my @records;
tie @records, 'Tie::File', "pile_out.txt";

# file containing data
$in_file = "fake_vals.fem";

# specific line number in the output file. The data from the input 
# file should be written at this line.
$seed_line = 10;

open(IN,"$in_file") or die("cannot open the log file for reading\n");

# NODE is the string to be matched with, in the data from the 
# input file

while(<IN>){######to read the input file
    $records[$seed_line] = "$_" if($_=~/\bNODE\b/i);  
    $seed_line++;
}


close(IN);

[download]

The result I need is the following to be printed in the output file, starting at line no. 11 in the output file. All lines in the input file, starting with the string NODE should be printed in the output file, without any empty line in between. 


 NODE              32        0.00000        0.00000       -1.90000
 NODE              33        0.00000        0.00000       -5.50000
 NODE              34        0.00000        0.00000       -9.00000
 NODE              35        0.00000        0.00000      -15.00000
 NODE              36        0.00000        0.00000      -18.90000
 NODE              37        0.00000        0.00000      -22.40000
 NODE              38        0.00000        0.00000      -25.90000
 NODE              39        0.00000        0.00000      -29.00000
 NODE              40        0.00000        0.00000      -32.50000
 NODE              41        0.00000        0.00000      -33.90000
 NODE              42        0.00000        0.00000      -62.90000

[download]

However, my code is printing newlines after very single line of data, in the output file, as shown below.

 

 NODE              32        0.00000        0.00000       -1.90000

 NODE              33        0.00000        0.00000       -5.50000

 NODE              34        0.00000        0.00000       -9.00000

 NODE              35        0.00000        0.00000      -15.00000

 NODE              36        0.00000        0.00000      -18.90000

 NODE              37        0.00000        0.00000      -22.40000

 NODE              38        0.00000        0.00000      -25.90000

 NODE              39        0.00000        0.00000      -29.00000

 NODE              40        0.00000        0.00000      -32.50000

 NODE              41        0.00000        0.00000      -33.90000

 NODE              42        0.00000        0.00000      -62.90000

[download]

Could you please tell me where I went wrong. This is the first time I have tried using Tie::File.

In reply to Newline's creep in, while using Tie::File by always_coys

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