Modifying data in variable length file

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

Hi, Sorry for asking a very basic question. I am trying to do the following with a test.DAT file. The file contains data in various columns that I want to replace to a constant or a random value. However in some cases there might be no data for that particular field length.

Problem:

Start Colum = 161 End Column = 190 , If there is text set to value MYTEXT

Start Column = 221 End Column = 230 , If there is text set to value 01/01/1980

Start Column = 231 End Column = 245 , If there is text set to value random 15 numbers

And leave everything else unchanged. Thanks you so much in advance.

Comment on Modifying data in variable length file

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Re: Modifying data in variable length file by wind (Priest) on Apr 27, 2011 at 22:28 UTC
Use Tie::File to manipulate each line of the file, and substr to access the columns you want to change.	[reply]
Re: Modifying data in variable length file by Tanktalus (Canon) on Apr 27, 2011 at 22:26 UTC
What have you tried? What does your data look like? Define "if there is text" - does that mean "if the line is this long"? Are spaces text? Because "variable length" and "strict column definitions" seem at odds to me.	[reply]
Re: Modifying data in variable length file by Anonymous Monk on Apr 27, 2011 at 22:26 UTC
Hi, Sorry for asking a very basic question. No need to be sorry for that, but even basic questions need to be effective :) How do I post a question effectively?	[reply]
Re: Modifying data in variable length file by nvivek (Vicar) on Apr 28, 2011 at 04:48 UTC
Tell how the columns are separated and what the delimiter is? Express your question with defined manner and if possible give example data. It will make you to get answer soon.	[reply]


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