Permuting a data frame

["Walter R. Paczkowski" <dataanalytics@earthlink.net>]

Good morning,

I have a trivial problem.  I want to permute the rows of a data frame with, 
say, five columns, each column having the same sequence of numbers, 1:n.  For 
example, I want to permute

x1  x2  x3  x4  x5
1    1     1    1    1
2    2     2    2    2
3    3     3    3    3
4    4     4    4    4
5    5     5    5    5

But, after the permutation, there can be no duplications in each row and, of 
course, each number in each column can appear only once in that column of the 
resulting data frame .  So, I would like something like

x1  x2  x3  x4  x5
1    5    4    3    2
2    1     5   4    3
3    2     1   5    4
4    3     2   1    5
5    4     3   2    1

except the problem I'm working on has 30 rows with five columns.

Is there an easy way to do this?  I tried the repeated application of sample 
with any and duplicated to check for the duplications, but this is very 
inefficient.

Thanks,

Walt Paczkowski
________________________

Walter R. Paczkowski, Ph.D.
Data Analytics Corp.
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