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

I hope with Schwartzian Transform...

Hi brothers,
I need sort @array in which is each element line of csv file - so values are separated by delimiter.like value1;value2;value3;value4 etc. And I need sort @array by certain valueX. But before comparing with <=> I must convert values to be numeric only. I know (it's given) that in value2 are only (in whole @array) number in this format xx.xxx.xxx,xx so I must use regex to remove points and replace comma by point. (but globaly I have many types of data fields, so script must be able to determine which regex use depending of given data type) But after sorting I want get as results not values changed by regex but sorted original values.....

I tested sort with mapbut I fail to get this to work :-(

ply if you know solution get me know..... THX to all

Li Tin O've Weedle
mad Tsort's philosopher

Replies are listed 'Best First'.
Re: sorting with Schwartzian Transform
by no_slogan (Deacon) on May 08, 2001 at 03:08 UTC
    How about 
        @sorted = map  { $_->[0] }
              sort { $a->[1] <=> $b->[1] }
              map  { [ $_, (split /[,.]/, $_)[$idx] ] } @array;

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    Where $idx is the column number you care about. If @array contains newlines, that might spew warnings... try 
        map { chomp(my $key = (split /[,.]/, $_)[$idx]);
          [ $_, $key ] } @array;

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[d/l]
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Re: sorting with Schwartzian Transform
by LiTinOveWeedle (Scribe) on May 08, 2001 at 03:15 UTC
    To request I try to specify more data - as sample.
    each element in array is in fact another array so there should be sometnig like:
    name;password;phonenumber;price

    with real datas something like this:
    LTOW;mypass;+420-2-312456;1.125.369,25

    I know (it is somewhere specify) that in phonenumber are only phonenumber in format like this one. When I want sort element in @array by phone number I must first convert number into number only format - remove + and - marks. Than I will be able to use <=> operator. But results should be @array with original phone numbers. Price field is the same problem - at first I must convert into numeric only and then I can sort.....

    Li Tin O've Weedle
    mad Tsort's philosopher

[reply]
      Any particular reason why telephone numbers need to be compared as numbers and not as strings? If you need to make more transformations, just keep chewing on $key in the map statement. 
          map { my $key = (split /,/, $_)[$idx];
          chomp $key;
          $key =~ s/[-+]//g;
          # and so on...
          [ $_, $key ] } @array;

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[d/l]
        Yeah no good example, prices is better.
        Many THX fot your answer....

        Li Tin O've Weedle
        mad Tsort's philosopher

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