2 use Scalar::Util 'blessed';
5 use Math::GSL::Errno qw/:all/;
6 use Math::GSL::BLAS qw/gsl_blas_ddot/;
8 '*' => \&_multiplication,
14 @EXPORT_all = qw/fopen fclose
15 gsl_vector_alloc gsl_vector_calloc gsl_vector_alloc_from_block gsl_vector_alloc_from_vector
16 gsl_vector_free gsl_vector_view_array gsl_vector_const_view_array gsl_vector_view_array_with_stride
17 gsl_vector_const_view_array_with_stride gsl_vector_subvector gsl_vector_subvector_wi gsl_vector_subvector_with_stride
18 gsl_vector_const_subvec gsl_vector_const_subvec gsl_vector_get gsl_vector_set
19 gsl_vector_ptr gsl_vector_const_ptr gsl_vector_set_zero gsl_vector_set_all
20 gsl_vector_set_basis gsl_vector_fread gsl_vector_fwrite gsl_vector_fscanf
21 gsl_vector_fprintf gsl_vector_memcpy gsl_vector_reverse gsl_vector_swap
22 gsl_vector_swap_elements gsl_vector_max gsl_vector_min gsl_vector_minmax
23 gsl_vector_max_index gsl_vector_min_index gsl_vector_minmax_index
24 gsl_vector_add gsl_vector_sub gsl_vector_mul gsl_vector_div
25 gsl_vector_scale gsl_vector_add_constant gsl_vector_isnull
26 gsl_vector_ispos gsl_vector_isneg gsl_vector_isnonneg
27 gsl_vector_float_alloc gsl_vector_float_calloc gsl_vector_float_alloc_from_block
28 gsl_vector_float_alloc_from_vector gsl_vector_float_free gsl_vector_float_view_array
29 gsl_vector_float_view_array_with_stride gsl_vector_float_const_view_array gsl_vector_float_const_view_array_with_stride
30 gsl_vector_float_subvector gsl_vector_float_subvector_with_stride gsl_vector_float_const_subvector
31 gsl_vector_float_const_subvector_with_stride gsl_vector_float_get gsl_vector_float_set gsl_vector_float_ptr
32 gsl_vector_float_const_ptr gsl_vector_float_set_zero gsl_vector_float_set_all gsl_vector_float_set_basis
33 gsl_vector_float_fread gsl_vector_float_fwrite gsl_vector_float_fscanf gsl_vector_float_fprintf
34 gsl_vector_float_memcpy gsl_vector_float_reverse gsl_vector_float_swap gsl_vector_float_swap_elements
35 gsl_vector_float_max gsl_vector_float_min gsl_vector_float_minmax gsl_vector_float_max_index gsl_vector_float_min_index
36 gsl_vector_float_minmax_index gsl_vector_float_add gsl_vector_float_sub gsl_vector_float_mul gsl_vector_float_div gsl_vector_float_scale
37 gsl_vector_float_add_constant gsl_vector_float_isnull gsl_vector_float_ispos gsl_vector_float_isneg gsl_vector_float_isnonneg
38 gsl_vector_complex_alloc gsl_vector_complex_calloc gsl_vector_complex_alloc_from_block gsl_vector_complex_alloc_from_vector
39 gsl_vector_complex_free gsl_vector_complex_view_array gsl_vector_complex_view_array_with_stride gsl_vector_complex_const_view_array
40 gsl_vector_complex_const_view_array_with_stride gsl_vector_complex_subvector gsl_vector_complex_subvector_with_stride
41 gsl_vector_complex_const_subvector gsl_vector_complex_const_subvector_with_stride gsl_vector_complex_real gsl_vector_complex_imag
42 gsl_vector_complex_const_real gsl_vector_complex_const_imag gsl_vector_complex_get gsl_vector_complex_set
43 gsl_vector_complex_ptr gsl_vector_complex_const_ptr gsl_vector_complex_set_zero gsl_vector_complex_set_all
44 gsl_vector_complex_set_basis gsl_vector_complex_fread gsl_vector_complex_fwrite gsl_vector_complex_fscanf
45 gsl_vector_complex_fprintf gsl_vector_complex_memcpy gsl_vector_complex_reverse gsl_vector_complex_swap
46 gsl_vector_complex_swap_elements gsl_vector_complex_isnull gsl_vector_complex_ispos gsl_vector_complex_isneg
48 @EXPORT_file =qw/ fopen fclose/;
49 @EXPORT_OK = (@EXPORT_all, @EXPORT_file);
50 %EXPORT_TAGS = ( file => \@EXPORT_file, all => \@EXPORT_all );
54 Math::GSL::Vector - Functions concerning vectors
58 use Math::GSL::Vector qw/:all/;
59 my $vec1 = Math::GSL::Vector->new([1, 7, 94, 15 ]);
61 my $vec3 = Math::GSL::Vector>new(10); # 10 element zero vector
62 my $vec4 = $vec1 + $vec2;
64 # set the element at index 1 to 9
65 # and the element at index 3 to 8
66 $vec3->set([ 1, 3 ], [ 9, 8 ]);
68 my @vec = $vec2->as_list; # return elements as Perl list
70 my $dot_product = $vec1 * $vec2;
71 my $length = $vec2->length;
72 my $first = $vec1->get(0);
77 =head1 Objected Oriented Interface to GSL Math::GSL::Vector
79 =head2 Math::GSL::Vector->new()
81 Creates a new Vector of the given size.
83 my $vector = Math::GSL::Matrix->new(3);
85 You can also create and set directly the values of the vector like this :
87 my $vector = Math::GSL::Vector->new([2,4,1]);
91 my ($class, $values) = @_;
92 my $length = $#$values;
95 if ( ref $values eq 'ARRAY' ){
96 die __PACKAGE__.'::new($x) - $x must be a nonempty array reference' if $length == -1;
97 $vector = gsl_vector_alloc($length+1);
98 map { gsl_vector_set($vector, $_, $values->[$_] ) } (0 .. $length);
99 $this->{_length} = $length+1;
100 } elsif ( (int($values) == $values) && ($values > 0)) {
101 $vector = gsl_vector_alloc($values);
102 gsl_vector_set_zero($vector);
103 $this->{_length} = $values;
105 die __PACKAGE__.'::new($x) - $x must be an int or array reference';
107 $this->{_vector} = $vector;
112 Get the underlying GSL vector object created by SWIG, useful for using gsl_vector_* functions which do not have an OO counterpart.
114 my $vector = Math::GSL::Vector->new(3);
115 my $gsl_vector = $vector->raw;
116 my $stuff = gsl_vector_get($gsl_vector, 1);
122 return $self->{_vector};
127 Returns the minimum value contained in the vector.
129 my $vector = Math::GSL::Vector->new([2,4,1]);
130 my $minimum = $vector->min;
136 return gsl_vector_min($self->raw);
141 Returns the minimum value contained in the vector.
143 my $vector = Math::GSL::Vector->new([2,4,1]);
144 my $maximum = $vector->max;
150 return gsl_vector_max($self->raw);
155 Returns the number of elements contained in the vector.
157 my $vector = Math::GSL::Vector->new([2,4,1]);
158 my $length = $vector->length;
162 sub length { my $self=shift; $self->{_length} }
166 Gets the content of a Math::GSL::Vector object as a Perl list.
168 my $vector = Math::GSL::Vector->new(3);
170 my @values = $vector->as_list;
175 $self->get( [ 0 .. $self->length - 1 ] );
180 Gets the value of an of a Math::GSL::Vector object.
182 my $vector = Math::GSL::Vector->new(3);
184 my @values = $vector->get(2);
186 You can also enter an array of indices to receive their corresponding values:
188 my $vector = Math::GSL::Vector->new(3);
190 my @values = $vector->get([0,2]);
195 my ($self, $indices) = @_;
196 return map { gsl_vector_get($self->raw, $_ ) } @$indices ;
201 Sets values of an of a Math::GSL::Vector object.
203 my $vector = Math::GSL::Vector->new(3);
204 $vector->set([1,2], [8,23]);
206 This sets the second and third value to 8 and 23.
211 my ($self, $indices, $values) = @_;
212 die (__PACKAGE__.'::set($indices, $values) - $indices and $values must be array references of the same length')
213 unless ( ref $indices eq 'ARRAY' && ref $values eq 'ARRAY' && $#$indices == $#$values );
215 map { gsl_vector_set($self->{_vector}, $indices->[$_], $values->[$_] ) } (0..$#$indices);
222 Returns a copy of the vector, which has the same length and values but resides at a different location in memory.
224 my $vector = Math::GSL::Vector->new([10 .. 20]);
225 my $copy = $vector->copy;
232 my $copy = Math::GSL::Vector->new( $self->length );
233 if ( gsl_vector_memcpy($copy->raw, $self->raw) != $GSL_SUCCESS ) {
234 croak "Math::GSL - error copying memory, aborting";
239 sub _multiplication {
240 my ($left,$right) = @_;
241 my $lcopy = $left->copy;
243 if ( blessed $right && $right->isa('Math::GSL::Vector') ) {
244 return $lcopy->dot_product($right);
246 gsl_vector_scale($lcopy->raw, $right);
252 my ($left, $right, $flip) = @_;
255 my $lcopy = $left->copy;
256 gsl_vector_scale($lcopy->raw, -1 );
257 gsl_vector_add_constant($lcopy->raw, $right);
260 return _addition($left, -1.0*$right);
265 my ($left, $right, $flip) = @_;
267 my $lcopy = $left->copy;
269 if ( blessed $right && $right->isa('Math::GSL::Vector') && blessed $left && $left->isa('Math::GSL::Vector') ) {
270 if ( $left->length == $right->length ) {
271 gsl_vector_add($lcopy->raw, $right->raw);
273 croak "Math::GSL - addition of vectors must be called with two objects vectors and must have the same length";
276 gsl_vector_add_constant($lcopy->raw, $right);
282 my ($left,$right) = @_;
284 if ( blessed $right && $right->isa('Math::GSL::Vector') &&
285 $left->length == $right->length ) {
286 my @l = $left->as_list;
287 my @r = $right->as_list;
288 map { $sum += $l[$_] * $r[$_] } (0..$#l);
291 croak "dot_product() must be called with two vectors";
296 my ($left,$right) = @_;
298 my ($status, $product) = gsl_blas_ddot($left->raw,$right->raw);
299 croak sprintf "Math::GSL::dot_product - %s", gsl_strerror($status) if ($status != $GSL_SUCCESS);
305 Here is a list of all the functions included in this module :
309 =item C<gsl_vector_alloc($x)> - create a vector of size $x
311 =item C<gsl_vector_calloc($x)> - create a vector of size $x and initializes all the elements of the vector to zero
313 =item C<gsl_vector_alloc_from_block>
315 =item C<gsl_vector_alloc_from_vector>
317 =item C<gsl_vector_free($v)> - free a previously allocated vector $v
319 =item C<gsl_vector_view_array($base, $n)> - This function returns a vector view of an array reference $base. The start of the new vector is given by $base and has $n elements. Mathematically, the i-th element of the new vector v' is given by, v'(i) = $base->[i] where the index i runs from 0 to $n-1. The array containing the elements of v is not owned by the new vector view. When the view goes out of scope the original array will continue to exist. The original memory can only be deallocated by freeing the original pointer base. Of course, the original array should not be deallocated while the view is still in use.
321 =item C<gsl_vector_const_view_array($base, $n)> - This function is equivalent to gsl_vector_view_array but can be used for arrays which are declared const.
323 =item C<gsl_vector_view_array_with_stride($base, $stride, $n)> - This function returns a vector view of an array reference $base with an additional $stride argument. The subvector is formed in the same way as for gsl_vector_view_array but the new vector has $n elements with a step-size of $stride from one element to the next in the original array. Mathematically, the i-th element of the new vector v' is given by, v'(i) = $base->[i*$stride] where the index i runs from 0 to $n-1. Note that the view gives direct access to the underlying elements of the original array. A vector view $view can be passed to any subroutine which takes a vector argument just as a directly allocated vector would be, using $view->{vector}.
325 =item C<gsl_vector_const_view_array_with_stride($base, $stride, $n)> - This function is equivalent to gsl_vector_view_array_with_stride but can be used for arrays which are declared const.
327 =item C<gsl_vector_subvector($v, $offset, $n)> - return a vector_view type which contains a subvector of $v, with a size of $size, starting from the $offset position
329 =item C<gsl_vector_subvector_with_stride($v, $offset, $stride, $size)> - return a vector_view type which contains a subvector of $v, with a size of $size, starting from the $offset position and with a $stride step between each element of $v
331 =item C<gsl_vector_const_subvector>
333 =item C<gsl_vector_get($v, $i)> - return the $i-th element of a vector $v
335 =item C<gsl_vector_set($v, $i, $x)> - return the vector $v with his $i-th element set to $x
337 =item C<gsl_vector_ptr>
339 =item C<gsl_vector_const_ptr>
341 =item C<gsl_vector_set_zero($v)> - set all the elements of $v to 0
343 =item C<gsl_vector_set_all($v, $x)> - set all the elements of $v to $x
345 =item C<gsl_vector_set_basis($v, $i)> - set all the elements of $v to 0 except for the $i-th element which is set to 1 and return 0 if the operation succeded, 1 otherwise.
347 =item C<gsl_vector_fread($file, $v)> - This function reads into the vector $v from the open stream $file opened with gsl_fopen function from the Math::GSL module in binary format. The vector $v must be preallocated with the correct length since the function uses the size of $v to determine how many bytes to read. The return value is 0 for success and 1 if there was a problem reading from the file.
349 =item C<gsl_vector_fwrite($file, $v)> - This function writes the elements of the vector $v to the stream $file opened with gsl_fopen function from the Math::GSL module in binary format. The return value is 0 for success and 1 if there was a problem writing to the file. Since the data is written in the native binary format it may not be portable between different architectures.
351 =item C<gsl_vector_fscanf($file, $v)> This function reads formatted data from the stream $file opened with gsl_fopen function from the Math::GSL module into the vector $v. The vector $v must be preallocated with the correct length since the function uses the size of $v to determine how many numbers to read. The function returns 0 for success and 1 if there was a problem reading from the file.
353 =item C<gsl_vector_fprintf($file, $v, $format)> -This function writes the elements of the vector $v line-by-line to the stream $file opened with gsl_fopen function from the Math::GSL module using the format specifier $format, which should be one of the "%g", "%e" or "%f" formats for floating point numbers and "%d" for integers. The function returns 0 for success and 1 if there was a problem writing to the file.
355 =item C<gsl_vector_memcpy($dest, $src)> - This function copies the elements of the vector $src into the vector $dest and return 0 if the opertaion succeded, 1 otherwise. The two vectors must have the same length.
357 =item C<gsl_vector_reverse($v)> - reverse the order of the elements of the vector $v and return 0 if the opertaion succeded, 1 otherwise
359 =item C<gsl_vector_swap($v, $v2)> - swap the values of the vectors $v and $v2 and return 0 if the opertaion succeded, 1 otherwise
361 =item C<gsl_vector_swap_elements($v, $i, $j)> - permute the elements at position $i and $j in the vector $v and return 0 if the operation succeded, 1 otherwise.
363 =item C<gsl_vector_max($v)> - return the maximum value in the vector $v
365 =item C<gsl_vector_min($v)> - return the minimum value in the vector $v
367 =item C<gsl_vector_minmax($v)> - return two values, the first is the minimum value in the vector $v and the second is the maximum value.
369 =item C<gsl_vector_max_index($v)> - return the position of the maximum value in the vector $v
371 =item C<gsl_vector_min_index($v)> - return the position of the minimum value in the vector $v
373 =item C<gsl_vector_minmax_index> - return two values, the first is the position of the minimum value in the vector $v and the second is the position of the maximum value.
375 =item C<gsl_vector_add($v, $v2)> - add the elements of $v2 to the elements of $v, the two vectors must have the same lenght and return 0 if the operation succeded, 1 otherwise.
377 =item C<gsl_vector_sub($v, $v2)> - substract the elements of $v2 from the elements of $v, the two vectors must have the same lenght and return 0 if the operation succeded, 1 otherwise.
379 =item C<gsl_vector_mul($v, $v2)> - multiply the elements of $v by the elements of $v2, the two vectors must have the same lenght and return 0 if the operation succeded, 1 otherwise.
381 =item C<gsl_vector_div($v, $v2)> - divides the elements of $v by the elements of $v2, the two vectors must have the same lenght and return 0 if the operation succeded, 1 otherwise.
383 =item C<gsl_vector_scale($v, $x)> - multiplty the elements of the vector $v by a constant $x and return 0 if the operation succeded, 1 otherwise.
385 =item C<gsl_vector_add_constant($v, $x)> - add a constant $x to the elements of the vector $v and return 0 if the operation succeded, 1 otherwise.
387 =item C<gsl_vector_isnull($v)> - verify if all the elements of the vector $v are null, return 0 if it's the case, 1 otherwise.
389 =item C<gsl_vector_ispos($v)> - verify if all the elements of the vector $v are positive, return 0 if it's the case, 1 otherwise.
391 =item C<gsl_vector_isneg($v)> - verify if all the elements of the vector $v are negative, return 0 if it's the case, 1 otherwise.
393 =item C<gsl_vector_isnonneg($v)> - verify if all the elements the vector $v are not negative, return 0 if it's the case, 1 otherwise.
397 You have to add the functions you want to use inside the qw /put_funtion_here / with spaces between each function. You can also write use Math::GSL::Complex qw/:all/ to use all avaible functions of the module.
400 Precision on the vector_view type : every modification you'll make on a vector_view will also modify the original vector.
401 For example, the following code will zero the even elements of the vector $v of length $size, while leaving the odd elements untouched :
405 =item C<$v_even= gsl_vector_subvector_with_stride ($v, 0, 2, $size/2);>
407 =item C<gsl_vector_set_zero ($v_even-E<gt>{vector});>
411 For more informations on the functions, we refer you to the GSL offcial documentation:
412 L<http://www.gnu.org/software/gsl/manual/html_node/>
414 Tip : search on google: site:http://www.gnu.org/software/gsl/manual/html_node/ name_of_the_function_you_want
418 Here is an example using both interfaces.
420 use Math::GSL::Vector qw/:all/;
422 print "We'll create this vector : [0,1,4,9,16] \n";
423 my $vector = Math::GSL::Vector->new([0,1,4,9,16]);
424 my ($min, $max) = gsl_vector_minmax_index($vector->raw);
426 print "We then check the index value of the maximum and minimum values of the vector. \n";
427 print "The index of the maximum should be 4 and we received $max \n";
428 print "The index of the minimum should be 0 and we received $min \n";
429 print "We'll then swap the first and the third elements of the vector \n";
431 gsl_vector_swap_elements($vector->raw, 0, 3);
432 my @got = $vector->as_list;
433 print "The vector should now be like this : [9,1,4,0,16] \n";
434 print "and we received : [ @got ]\n";
438 Jonathan Leto <jonathan@leto.net> and Thierry Moisan <thierry.moisan@gmail.com>
440 =head1 COPYRIGHT AND LICENSE
442 Copyright (C) 2008 Jonathan Leto and Thierry Moisan
444 This program is free software; you can redistribute it and/or modify it
445 under the same terms as Perl itself.