Programmer Guide/Command Reference/EVAL/shuffle: Difference between revisions
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{{DISPLAYTITLE:{{SUBPAGENAME}}}} | {{DISPLAYTITLE:{{SUBPAGENAME}}}} | ||
Create a ''shuffled'' version of a set. | Create a ''shuffled'' version of a set. | ||
;Usage: <code>shuffle(''x'' {, ''n'' {, ''once'' { ''seed''}}})</code> | |||
;Usage: | |||
:;''x'': the set to be shuffled; must be a vector or matrix | :;''x'': the set to be shuffled; must be a vector or matrix | ||
:;''n'': the number of row exchanges applied top ''x''; <code>0 < ''n''</code> (default=<code>nrow(''x'')/2) | :;''n'': the number of row exchanges applied top ''x''; <code>0 < ''n''</code> (default=<code>nrow(''x'')/2) | ||
Line 9: | Line 8: | ||
::''once''!=0: the number of exchanges of a row is limited to 1 | ::''once''!=0: the number of exchanges of a row is limited to 1 | ||
:;''seed'': if this value is not equal ''0'', it is used to initialize the random number generator used to select the rows to be exchanged | :;''seed'': if this value is not equal ''0'', it is used to initialize the random number generator used to select the rows to be exchanged | ||
;Result: The result has the same type and content as ''x'', but the order of the rows is changed (''shuffeld'') randomly. To shuffle the row indices, ''n'' times two randomly selected rows are exchanged. | ;Result: The result has the same type and content as ''x'', but the order of the rows is changed (''shuffeld'') randomly. To shuffle the row indices, ''n'' times two randomly selected rows are exchanged. | ||
;See also: [[../rand|rand]], [[../grand|grand]], [[../sample|sample]], [[../sort|sort]] | |||
[[../#Functions|<function list>]] | |||
Revision as of 11:48, 21 April 2011
Create a shuffled version of a set.
- Usage
shuffle(x {, n {, once { seed}}})
- x
- the set to be shuffled; must be a vector or matrix
- n
- the number of row exchanges applied top x;
0 < n
(default=nrow(x)/2)
- once
- change row position only once
- once==0: the number of exchanges of a row is not limited
- once!=0: the number of exchanges of a row is limited to 1
- seed
- if this value is not equal 0, it is used to initialize the random number generator used to select the rows to be exchanged