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Source for wiki CombinationsCowan version 1

author

cowan

comment

ipnr

127.11.51.1

name

CombinationsCowan

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text

{{{
#!html
<dl>
<dt><a name="index-permutations_002dof"></a><code>make-permutation-generator</code><i> vector</i></dt>
<dd><p>Returns a generator that yields random permutations of <var>vector</var>.
</p>
<table><tr><td>&nbsp;</td><td><pre class="example">(generator-&gt;list (make-permutation-generator '(1 2 3)) 3)
 &rArr; ((1 2 3) (2 3 1) (3 2 1))

(generator-&gt;list (make-permutation-generator &quot;abc&quot;) 3)
 &rArr; (&quot;cba&quot; &quot;cba&quot; &quot;cab&quot;)
</pre></td></tr></table>
</dd></dl>

<dl>
<dt><a name="index-combinations_002dof"></a><code>make-combination-generator</code><i> size vector</i></dt>
<dd><p>Returns a generator that yields vectors of <var>size</var> elements
randomly picked from <var>vector</var>.
</p>
<table><tr><td>&nbsp;</td><td><pre class="example">(generator-&gt;list (make-combination-generatorh 2 #(a b c)) 5)
 &rArr; (#(a c) #(a b) #(a c) #(b a) #(a c))

(generator-&gt;list (make-combination-generator 2 '#(a b c)) 5)
 &rArr; (#(a c) #(b c) #(c b) #(b a) #(b c))
</pre></td></tr></table>
</dd></dl>
}}}

time

2017-06-16 01:58:11