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

Hi Brethren,
The following code
print join "\n", map {"$_->[0]\t " . join ' ', @{$_->[1]}} @UnNum;
Prints the following data to screen
91   50, This is the first line
56   46, This is my second line

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I would like to print this data to file omitting the first numbers so that my data is 
 
50, This is my first line 
46, This is my second line

[download]

Any ideas much appreciated
Many Thanks

Replies are listed 'Best First'.
Re: Printing Map to file
by lima1 (Curate) on Mar 25, 2006 at 20:50 UTC
    1. if you post code that uses some complex data structures, provide an example, e.g. 
     
my @UnNum = ( [ 0, [1,2,3] ], [ 0, [1,2,3] ]);

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    2. if you don't understand some code others post here, try to read the perldoc (e.g. perldoc -f map) and then ask again if sth is still unclear.

    what this join/map line does (from inner to out):

    join ' ', @{$_->[1]}

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    Simply generate a string with all elements in the second element (u know what i mean ;) ), the arrayref, seperated by blank. 
    map {"$_->[0]\t " . join ' ', @{$_->[1]}} @UnNum;

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    now generate an array with the same number of elements like @UnNum. the elements are now a string where the first array element is seperated by a tab from the string generated with join. 
    print join "\n", map {"$_->[0]\t " . join ' ', @{$_->[1]}} @UnNum;

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    now generate a string out of this new array, seperated by newline and print it.

    if you understand this, then you know the answer to your question.

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[d/l]
[select]
      That's just what I was hoping for.
      Too often the answers just give a bit of code: no comment! I know it takes a lot longer to comment the code but it makes a big difference to someone like me who is new to programming.
      Thanks again for your time. I now understand what the code was doing.
[reply]
Re: Printing Map to file
by explorer (Chaplain) on Mar 25, 2006 at 20:37 UTC
    print join "\n", map { join ' ', @{$_->[1]}} @UnNum;
[reply]
[d/l]

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