Dear Monks--

I have a an array of an arrays that looks like this: 
$courselist[$courseindex] = [$Institution, $CourseNumber, $Professor, 
+$CourseTitle, $Enrollment]

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I'd like to sort it by $Institution and within that sort by $CourseNumber (and possibly other values). E.g. the array starts like: 
$courseindex[0] = ["UM", "CS 34", ......]
$courseindex[1] = ["AC", "PHIL 13", ....]
$courseindex[2] = ["UM:, "BIO 567', ....]

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and I want it to end like this: 
$courseindex[0] = ["AC", "PHIL 13", ....]
$courseindex[1] = ["UM", "BIO 567', ....]
$courseindex[2] = ["UM", "CS 34", ......]

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I haven't been able to figure out how to do it.

I tried using something like: 
@courselist = sort {$$a[n] cmp $$b[n]} @courselist;

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(with various values for n) which worked for me in another program with a similar, but less complex problem, but in this one I'm getting this error message:

"Modification of a read-only value attempted"

Which I can't figure out.

Anyway, that may be the wrong way to go about this problem at hand.

Any clarifications or suggestions would be welcome!

Thanks!

In reply to sorting an array of an arrays by Gnat53

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