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NAME

Math::GSL::Sort - Functions for sorting data

SYNOPSIS

    use Math::GSL::Sort qw/:all/;
    my $x       = [ 2**15, 1.67, 20e5, -17, 6900, 1/3 , 42e-10 ];
    my $sorted  = gsl_sort($x, 1, $#$x+1 );
    my $numbers = [ map { rand(100) } (1..100) ];
    my ($status, $smallest10) = gsl_sort_smallest($array, 10, $x, 1, $#$x+1);

DESCRIPTION

Here is a list of all the functions included in this module :

  • gsl_sort_vector($v)

     This function sorts the elements of the vector $v into ascending numerical order. 
  • gsl_sort_vector_index($p, $v)

     This function indirectly sorts the elements of the vector $v into ascending
     order, storing the resulting permutation in $p. The elements of $p give the
     index of the vector element which would have been stored in that position if
     the vector had been sorted in place. The first element of $p gives the index
     of the least element in $v, and the last element of $p gives the index of the
     greatest element in $v. The vector $v is not changed. 
  • gsl_sort_vector_smallest($array, $k, $vector)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     $k smallest elements of the vector $v. $k must be less than or equal to the
     length of the vector $v.
  • gsl_sort_vector_smallest_index($p, $k, $v)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     indices of the $k smallest elements of the vector $v. $p must be a prealocated
     array reference. This should be removed in further versions. $k must be less
     than or equal to the length of the vector $v. 
  • gsl_sort_vector_largest($array, $k, $vector)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     $k largest elements of the vector $v. $k must be less than or equal to the
     length of the vector $v.
  • gsl_sort_vector_largest_index($p, $k, $v)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     indices of the $k largest elements of the vector $v. $p must be a prealocated
     array reference. This should be removed in further versions. $k must be less
     than or equal to the length of the vector $v. 
  • gsl_sort($data, $stride, $n)

     This function returns an array reference to the sorted $n elements of the
     array $data with stride $stride into ascending numerical order.
  • gsl_sort_index($p, $data, $stride, $n)

     This function indirectly sorts the $n elements of the array $data with stride
     $stride into ascending order, outputting the permutation in the foram of an
     array. $p must be a prealocated array reference. This should be removed in
     further versions. The array $data is not changed.
  • gsl_sort_smallest($array, $k, $data, $stride, $n)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     $k smallest elements of the array $data, of size $n and stride $stride, in
     ascending numerical. The size $k of the subset must be less than or equal to
     $n. The data $src is not modified by this operation. $array must be a
     prealocated array reference. This should be removed in further versions.
  • gsl_sort_smallest_index($p, $k, $src, $stride, $n)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     indices of the $k smallest elements of the array $src, of size $n and stride
     $stride. The indices are chosen so that the corresponding data is in ascending
     numerical order. $k must be less than or equal to $n. The data $src is not
     modified by this operation. $p must be a prealocated array reference. This
     should be removed in further versions. 
  • gsl_sort_largest($array, $k, $data, $stride, $n)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     $k largest elements of the array $data, of size $n and stride $stride, in
     ascending numerical. The size $k of the subset must be less than or equal to
     $n. The data $src is not modified by this operation. $array must be a
     prealocated array reference. This should be removed in further versions.
  • gsl_sort_largest_index($p, $k, $src, $stride, $n)

     This function outputs 0 if the operation succeeded, 1 otherwise and then the
     indices of the $k largest elements of the array $src, of size $n and stride
     $stride. The indices are chosen so that the corresponding data is in ascending
     numerical order. $k must be less than or equal to $n. The data $src is not
     modified by this operation. $p must be a prealocated array reference. This
     should be removed in further versions. 
 Here is a complete list of all tags for this module :
all
plain
vector
 For more informations on the functions, we refer you to the GSL offcial documentation: 
 L<http://www.gnu.org/software/gsl/manual/html_node/>

 Tip : search on google: L<http://www.gnu.org/software/gsl/manual/html_node/name_of_the_function_you_want>

PERFORMANCE

 In the source code of Math::GSL, the file "examples/benchmark/sort" compares
 the performance of gsl_sort() to Perl's builtin sort() function. It's first
 argument is the number of iterations and the second is the size of the array
 of numbers to sort. For example, to see a benchmark of 1000 iterations for 
 arrays of size 50000 you would type

    ./examples/benchmark/sort 1000 50000

 Initial benchmarks indicate just slightly above a 2x performance increase
 over sort() for arrays of between 5000 and 50000 elements. This may mostly
 be due to the fact that gsl_sort() takes and returns a reference while sort()
 takes and returns a plain list.

AUTHORS

Jonathan Leto <jonathan@leto.net> and Thierry Moisan <thierry.moisan@gmail.com>

COPYRIGHT AND LICENSE

Copyright (C) 2008-2009 Jonathan Leto and Thierry Moisan

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.