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doc: Various docstring improvements before 3.6.0 release. * NEWS, aspell-octave.en.pws, intro.txi, oop.txi, testfun.txi, tips.txi, FIRfilter.m, FIRfilter_aggregation.m, polynomial.m, polynomial_superiorto.m, usejava.m, pcg.m, pcr.m, nchoosek.m, validatestring.m, assert.m, weekday.m, cellfun.cc, error.cc, strfns.cc: Various docstring improvements before 3.6.0 release.
author Rik <octave@nomad.inbox5.com>
date Wed, 21 Dec 2011 19:46:57 -0800
parents a1e386b9ef4b
children 951eacaf9381
comparison
equal deleted inserted replaced
14092:22c50cbad2ce 14093:050bc580cb60
687 example of which is the @code{nchoosek} function. The Texinfo 687 example of which is the @code{nchoosek} function. The Texinfo
688 documentation string for @code{nchoosek} is 688 documentation string for @code{nchoosek} is
689 689
690 @example 690 @example
691 -*- texinfo -*- 691 -*- texinfo -*-
692 @@deftypefn @{Function File@} @{@} nchoosek (@@var@{n@}, @@var@{k@}) 692 @@deftypefn @{Function File@} @{@@var@{c@} =@} nchoosek (@@var@{n@}, @@var@{k@})
693 693 @@deftypefnx @{Function File@} @{@@var@{c@} =@} nchoosek (@@var@{set@}, @@var@{k@})
694 Compute the binomial coefficient or all combinations of 694
695 @@var@{n@}. If @@var@{n@} is a scalar then, calculate the 695 Compute the binomial coefficient or all combinations of a set of items.
696 binomial coefficient of @@var@{n@} and @@var@{k@}, defined as 696
697 697 If @@var@{n@} is a scalar then calculate the binomial coefficient
698 of @@var@{n@} and @@var@{k@} which is defined as
698 @@tex 699 @@tex
699 $$ 700 $$
700 @{n \choose k@} = @{n (n-1) (n-2) \cdots (n-k+1) \over k!@} 701 @{n \choose k@} = @{n (n-1) (n-2) \cdots (n-k+1) \over k!@}
702 = @{n! \over k! (n-k)!@}
701 $$ 703 $$
702 @@end tex 704 @@end tex
703 @@ifnottex 705 @@ifnottex
704 706
705 @@example 707 @@example
706 @@group 708 @@group
707 / \ 709 / \
708 | n | n (n-1) (n-2) @dots{} (n-k+1) 710 | n | n (n-1) (n-2) @@dots@{@} (n-k+1) n!
709 | | = ------------------------- 711 | | = ------------------------- = ---------
710 | k | k! 712 | k | k! k! (n-k)!
711 \ / 713 \ /
712 @@end group 714 @@end group
713 @@end example 715 @@end example
716
714 @@end ifnottex 717 @@end ifnottex
715 718 @@noindent
716 If @@var@{n@} is a vector, this generates all combinations 719 This is the number of combinations of @@var@{n@} items taken in groups of
717 of the elements of @@var@{n@}, taken @@var@{k@} at a time, 720 size @@var@{k@}.
718 one row per combination. The resulting @@var@{c@} has size 721
719 @@code@{[nchoosek (length (@@var@{n@}),@@var@{k@}), @@var@{k@}]@}. 722 If the first argument is a vector, @@var@{set@}, then generate all
720 723 combinations of the elements of @@var@{set@}, taken @@var@{k@} at a time, with
721 @@code@{nchoosek@} works only for non-negative integer arguments; use 724 one row per combination. The result @@var@{c@} has @@var@{k@} columns and
722 @@code@{bincoeff@} for non-integer scalar arguments and for using vector 725 @@w@{@@code@{nchoosek (length (@@var@{set@}), @@var@{k@})@}@} rows.
723 arguments to compute many coefficients at once. 726
724 727 For example:
725 @@seealso@{bincoeff@} 728
729 How many ways can three items be grouped into pairs?
730
731 @@example
732 @@group
733 nchoosek (3, 2)
734 @@result@{@} 3
735 @@end group
736 @@end example
737
738 What are the possible pairs?
739
740 @@example
741 @@group
742 nchoosek (1:3, 2)
743 @@result@{@} 1 2
744 1 3
745 2 3
746 @@end group
747 @@end example
748
749 @@code@{nchoosek@} works only for non-negative, integer arguments. Use
750 @@code@{bincoeff@} for non-integer and negative scalar arguments, or for
751 computing many binomial coefficients at once with vector inputs
752 for @@var@{n@} or @@var@{k@}.
753
754 @@seealso@{bincoeff, perms@}
726 @@end deftypefn 755 @@end deftypefn
727 @end example 756 @end example
728 757 @noindent
729 which demonstrates most of the concepts discussed above. 758 which demonstrates most of the concepts discussed above.
730 @iftex 759 @iftex
731 This documentation string renders as 760 This documentation string renders as
732 761
733 @c Note actually use the output of info below rather than try and 762 @c Note: use the actual output of info below, rather than try and
734 @c reproduce it here to prevent it looking different than how it would 763 @c reproduce it here to prevent it looking different from how it would
735 @c appear with info. 764 @c appear with info.
736 @example 765 @example
737 @group
738 -- Function File: C = nchoosek (N, K) 766 -- Function File: C = nchoosek (N, K)
739 Compute the binomial coefficient or all combinations 767 -- Function File: C = nchoosek (SET, K)
740 of N. If N is a scalar then, calculate the binomial 768 Compute the binomial coefficient or all combinations of a set of
741 coefficient of N and K, defined as 769 items.
770
771 If N is a scalar then calculate the binomial coefficient of N and
772 K which is defined as
742 773
743 / \ 774 / \
744 | n | n (n-1) (n-2) @dots{} (n-k+1) n! 775 | n | n (n-1) (n-2) ... (n-k+1) n!
745 | | = ------------------------- = --------- 776 | | = ------------------------- = ---------
746 | k | k! k! (n-k)! 777 | k | k! k! (n-k)!
747 \ / 778 \ /
748 779
749 If N is a vector generate all combinations of the 780 This is the number of combinations of N items taken in groups of
750 elements of N, taken K at a time, one row per 781 size K.
751 combination. The resulting C has size `[nchoosek 782
752 (length (N), K), K]'. 783 If the first argument is a vector, SET, then generate all
753 784 combinations of the elements of SET, taken K at a time, with one
754 `nchoosek' works only for non-negative integer 785 row per combination. The result C has K columns and
755 arguments; use `bincoeff' for non-integer scalar 786 `nchoosek (length (SET), K)' rows.
756 arguments and for using vector arguments to compute 787
757 many coefficients at once. 788 For example:
758 789
759 See also: bincoeff. 790 How many ways can three items be grouped into pairs?
760 @end group 791
761 @end example 792 nchoosek (3, 2)
762 793 => 3
763 using info, whereas in a printed documentation using @TeX{} it will appear 794
764 as 795 What are the possible pairs?
765 796
766 @deftypefn {Function File} {@var{c} =} nchoosek (@var{n}, @var{k}) 797 nchoosek (1:3, 2)
767 798 => 1 2
768 Compute the binomial coefficient or all combinations of @var{n}. 799 1 3
769 If @var{n} is a scalar then, calculate the binomial coefficient 800 2 3
770 of @var{n} and @var{k}, defined as 801
802 `nchoosek' works only for non-negative, integer arguments. Use
803 `bincoeff' for non-integer and negative scalar arguments, or for
804 computing many binomial coefficients at once with vector inputs
805 for N or K.
806
807 See also: bincoeff, perms
808 @end example
809 @noindent
810 using info, whereas in a printed documentation using @TeX{} it will
811 appear as
812
813 @deftypefn {Function File} {@var{c} =} nchoosek (@var{n}, @var{k})
814 @deftypefnx {Function File} {@var{c} =} nchoosek (@var{set}, @var{k})
815
816 Compute the binomial coefficient or all combinations of a set of items.
817
818 If @var{n} is a scalar then calculate the binomial coefficient
819 of @var{n} and @var{k} which is defined as
771 820
772 @tex 821 @tex
773 $$ 822 $$
774 {n \choose k} = {n (n-1) (n-2) \cdots (n-k+1) \over k!} 823 {n \choose k} = {n (n-1) (n-2) \cdots (n-k+1) \over k!}
824 = {n! \over k! (n-k)!}
775 $$ 825 $$
776 @end tex 826 @end tex
777 827
778 If @var{n} is a vector generate all combinations of the elements 828 @noindent
779 of @var{n}, taken @var{k} at a time, one row per combination. The 829 This is the number of combinations of @var{n} items taken in groups of
780 resulting @var{c} has size @code{[nchoosek (length (@var{n}), 830 size @var{k}.
781 @var{k}), @var{k}]}. 831
782 832 If the first argument is a vector, @var{set}, then generate all
783 @code{nchoosek} works only for non-negative integer arguments; use 833 combinations of the elements of @var{set}, taken @var{k} at a time, with
784 @code{bincoeff} for non-integer scalar arguments and for using vector 834 one row per combination. The result @var{c} has @var{k} columns and
785 arguments to compute many coefficients at once. 835 @w{@code{nchoosek (length (@var{set}), @var{k})}} rows.
786 836
787 @seealso{bincoeff} 837 For example:
838
839 How many ways can three items be grouped into pairs?
840
841 @example
842 @group
843 nchoosek (3, 2)
844 @result{} 3
845 @end group
846 @end example
847
848 What are the possible pairs?
849
850 @example
851 @group
852 nchoosek (1:3, 2)
853 @result{} 1 2
854 1 3
855 2 3
856 @end group
857 @end example
858
859 @code{nchoosek} works only for non-negative, integer arguments. Use
860 @code{bincoeff} for non-integer and negative scalar arguments, or for
861 computing many binomial coefficients at once with vector inputs for @var{n}
862 or @var{k}.
863
864 @seealso{bincoeff, perms}
788 @end deftypefn 865 @end deftypefn
789 866
790 @end iftex 867 @end iftex