sortnd
Sort the elements of an array along a particular direction.
[y,ind]=sortnd(a,dim)
Inputs 
a 
Any array. 
dim 
An integer between 1 and the number of dimensions of a . 
Outputs 
y 
The sorted input along the diemnsion dim as defined below. 
ind 
The array of indices containing the information sufficient to reconstruct y from a .

Description
The result is such that the vector y[i,j,k,..,:, p,q,..]
(where
i,j,..
are scalar integers, and :
appears at the position indexed by dim
)
is the sorted version of the vector a[i,j,k,..,:, p,q,..]
.
The array of indices is such that with M=ind[i,j,...,:, p,q,..]
,
the vector y[i,j,k,..,:, p,q,..]
is identical to
the vector a[i,j,k,..,M, p,q,..]
.
The call shuffle(a,ind,dim)
can be used to reconstruct y
from the other
parameters.
Example
>>a=fix(rand(2,4,3)*100)
>>a
[:,1:4, 1]
29 27 68 38
47 47 94 92
[:,1:4, 2]
40 96 52 9
6 70 73 1
[:,1:4, 3]
25 36 98 96
97 14 73 17
>>(b,ind)=sortnd(a,2)
>>// Note that the rows are sorted
>>b
[:,1:4, 1]
27 29 38 68
47 47 92 94
[:,1:4, 2]
9 40 52 96
1 6 70 73
[:,1:4, 3]
25 36 96 98
14 17 73 97
>>shuffle(a,ind,2)
[:,1:4, 1]
27 29 38 68
47 47 92 94
[:,1:4, 2]
9 40 52 96
1 6 70 73
[:,1:4, 3]
25 36 96 98
14 17 73 97