Shorten the list of computation

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

I have quite a dozen of repeated formulas

     $list_total_perla+= $perla;
     $list_total_perlb+= $perlb;
     $list_total_perlc+= $perlc;
     $list_total_perld+= $perld;
     $list_total_perle+= $perle;
     $list_total_perld+= $perld;
[download]

Tried using an array

@shorten = (perla, perlb, perlc, perld, perle, perld);
[download]

to shorten the formula. But I am having difficulty calling the variables e.g. $list_total_perld

Comment on Shorten the list of computation Select or Download Code

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Re: Shorten the list of computation by BrowserUk (Patriarch) on May 12, 2003 at 06:16 UTC
Instead of using loads of seperate variable, use arrays: `my ( @list_total_perl, @perl ); @perl = list_from_wherever(); $list_total_perl[ $_ ] += $perl[ $_ ] for 0 .. $#perl;` [download] Or if you insist on indexing things with letters, use hashes. `my ( %list_total_perl, %perl ); @perl{ 'a' .. 'e' } = list_from_wherever(); $list_total_perl{ $_ } += $list{ $_ } for 'a' .. 'e';` [download] Examine what is said, not who speaks. "Efficiency is intelligent laziness." -David Dunham "When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller	[reply] [d/l] [select]
Re: Shorten the list of computation by Zaxo (Archbishop) on May 12, 2003 at 06:14 UTC
You appear to use 'a'..'e' as labels indicating some order. An array, `@list_totals`, would make that much tidier, or else a hash if the labels are meaningful. Your variable names seem to edge toward symbolic references in design, which is not the way to go with it. After Compline, Zaxo	[reply]
Re: Shorten the list of computation by Aristotle (Chancellor) on May 12, 2003 at 06:05 UTC
It's completely unclear what your problem is. What are you trying to do, what does not work as expected, and what does happen? Makeshifts last the longest.	[reply]
Re: Shorten the list of computation by CombatSquirrel (Hermit) on May 13, 2003 at 15:24 UTC
If your variables have utterly different names and completely different purposes, which prevents from putting them into one array, you might want to use something like `{ no strict 'refs'; my @incs = qw( index chapter index pages names ); for my $i (@incs) { ${"total_$i"} += $$i; } }` [download] It would still be better if you first built up an hash with hard references and then iterate through the command list `my %incs = (index => [ \$index, \$total_index ], chapter => [ \$chapter, \$total_chapter ], pages => [ \$pages, \$total_pages ], names => [ \$names, \$total_names ] ); my @incs = qw( index chapter index pages names ); ${$incs{$_}->[1]} += ${$incs{$_}->[0]} for (@incs);` [download] This does not violate use strict (assuming that you have declared all your variables before);	[reply] [d/l] [select]