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the unsorted array is @array, but what are $a and $b?
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the unsorted array is @array, but what are $a and $b?

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Perl's sort operator can take a comparison function as one of its parameters, in case you want something other than the default lexical sort. The $a and $b are variables with which the comparison function is called containing the left hand side and the right hand side, respectively. It's a convention left over from very early versions of Perl.
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Perl's sort operator can take a comparison function as one of its parameters, in case you want something other than the default lexical sort. The $a and $b are variables with which the comparison function is called containing the left hand side and the right hand side, respectively. It's a convention left over from very early versions of Perl.

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My array is made by n rows and 9 columns, and I need to sort the whole array with ref to the 5th column (id=4).<br />
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How?<br />
<br />

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My array is made by n rows and 9 columns, and I need to sort the whole array with ref to the 5th column (id=4).

How?



Sorting a multi-dimensional array

Perl is a high-level, general-purpose, interpreted, dynamic programming languages with over 25 years of development. Perl 5 runs on over 100 platforms from portables to mainframes and is suitable for both rapid prototyping and large-scale development projects.  Perl gained widespread popularity as a Common Gateway Interface (CGI) scripting language, in part due to its regular expression and string parsing abilities. In addition to CGI, Perl is used for graphics programming, system administration, network programming, finance, bioinformatics, and other applications.