How to get the column from lines

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

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Re: How to get the column from lines by Corion (Patriarch) on Apr 14, 2014 at 11:44 UTC
What is this line supposed to do? `my @table = push (split ( / /, @lines) );` [download] If you `use warnings`, Perl will tell you that this line makes little sense: `Useless use of push with no values at -e line 1.` [download] Maybe you can explain what error message you get and how you have tried to address the error message?	[reply] [d/l] [select]
Re: How to get the column from lines by Lennotoecom (Pilgrim) on Apr 14, 2014 at 12:30 UTC
`@a = ( 'a b c d e', 'f g h i j', 'k l m n o', 'p q r s t', 'u v w x y' ); @b = map (join(' ', (split /\s/)[1, 4]), @a); print "$_\n" for @b;` [download] output `b e g j l o q t v y` [download]	[reply] [d/l] [select]
Re: How to get the column from lines by GotToBTru (Prior) on Apr 14, 2014 at 16:11 UTC
Firstly, it would be very helpful to see an example of the data. Secondly, zero-based indexing trips up a lot of people. `(split / /)[2,5]` will give you the 3rd and 6th columns of your data.	[reply] [d/l]
Re^2: How to get the column from lines by hippo (Bishop) on Apr 14, 2014 at 16:19 UTC
Best guess is that this is an example of the data.	[reply]
Re^2: How to get the column from lines by Bloodnok (Vicar) on Apr 14, 2014 at 16:37 UTC
My best guess would actually be Need a help for perl coding, contrary to hippo's suggestion, but that indicated by hippo has it presented somewhat more understandably/sensibly. .oO(Not looked, but one wonders if multiple, marginally differently posed, postings is/maybe/should be covered in How do I post a question effectively??) A user level that continues to overstate my experience :-))	[reply]
Re: How to get the column from lines by Laurent_R (Canon) on Apr 14, 2014 at 16:01 UTC
If you need to store the data in a new array (I'll assume an array of arrays), you could do this (reusing the data kindly provided by Lennotoecom): `my @table = ('a b c d e', 'f g h i j', 'k l m n o', 'p q r s t', 'u +v w x y'); my @table2 = map { [(split / /, $_)[1, 4]] } @table;` [download] The @table2 array now looks like this: `0 ARRAY(0x803cc6d8) 0 ARRAY(0x8042f630) 0 'b' 1 'e' 1 ARRAY(0x8042f828) 0 'g' 1 'j' 2 ARRAY(0x8042f840) 0 'l' 1 'o' 3 ARRAY(0x8042f540) 0 'q' 1 't' 4 ARRAY(0x8042f870) 0 'v' 1 'y'` [download] If you want an array of lines, changing the second line to: `my @table2 = map { join " ", (split / /, $_)[1, 4] } @table;` [download] And the resulting array is now: `0 'b e' 1 'g j' 2 'l o' 3 'q t' 4 'v y'` [download] Edit: I did not look at it very carefully at the time, but I see now that the second solution I suggested just above is almost the same as the one suggested by Lennotoecom. Sorry for repeating almost the same thing, although this was not intentional.	[reply] [d/l] [select]


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