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eliminate more simple uses of error_state * ov-classdef.cc: Eliminate simple uses of error_state.
author John W. Eaton <jwe@octave.org>
date Tue, 06 Oct 2015 00:20:02 -0400
parents 4197fc428c7d
children
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4197fc428c7d maint: Update copyright notices for 2015.
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1 @c Copyright (C) 1996-2015 John W. Eaton
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2 @c
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3 @c This file is part of Octave.
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4 @c
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5 @c Octave is free software; you can redistribute it and/or modify it
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6 @c under the terms of the GNU General Public License as published by the
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7 @c Free Software Foundation; either version 3 of the License, or (at
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8 @c your option) any later version.
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9 @c
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10 @c Octave is distributed in the hope that it will be useful, but WITHOUT
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11 @c ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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12 @c FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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13 @c for more details.
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14 @c
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15 @c You should have received a copy of the GNU General Public License
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16 @c along with Octave; see the file COPYING. If not, see
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17 @c <http://www.gnu.org/licenses/>.
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18
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19 @node Sets
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20 @chapter Sets
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21
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22 Octave has a number of functions for managing sets of data. A set is defined
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23 as a collection of unique elements and is typically represented by a vector of
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24 numbers sorted in ascending order. Any vector or matrix can be converted to a
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25 set by removing duplicates through the use of the @code{unique} function.
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26 However, it isn't necessary to explicitly create a set as all of the functions
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27 which operate on sets will convert their input to a set before proceeding.
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28
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29 @DOCSTRING(unique)
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30
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31 @menu
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32 * Set Operations::
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33 @end menu
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34
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35 @node Set Operations
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36 @section Set Operations
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37
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38 Octave supports several basic set operations. Octave can compute the union,
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39 intersection, and difference of two sets. Octave also supports the
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40 @emph{Exclusive Or} set operation.
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41
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42 The functions for set operations all work in the same way by accepting two
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43 input sets and returning a third set. As an example, assume that @code{a} and
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44 @code{b} contains two sets, then
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45
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46 @example
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47 union (a, b)
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48 @end example
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49
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50 @noindent
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51 computes the union of the two sets.
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52
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53 Finally, determining whether elements belong to a set can be done with the
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54 @code{ismember} function. Because sets are ordered this operation is very
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55 efficient and is of order O(log2(n)) which is preferable to the @code{find}
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56 function which is of order O(n).
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57
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58 @DOCSTRING(intersect)
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59
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60 @DOCSTRING(union)
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61
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62 @DOCSTRING(setdiff)
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63
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64 @DOCSTRING(setxor)
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65
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66 @DOCSTRING(ismember)
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67
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68 @DOCSTRING(powerset)