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Usage
Computes the standard deviation of an array along a given
dimension. The general syntax for its use is
y = std(x,d)
where x is an n-dimensions array of numerical type. The
output is of the same numerical type as the input. The
argument d is optional, and denotes the dimension along
which to take the variance. The output y is the same size as
x, except that it is singular along the mean direction. So,
for example, if x is a 3 x 3 x 4 array, and we compute the
mean along dimension d=2, then the output is of size 3 x 1 x
4.
Example
The following piece of code demonstrates various uses of the
std function
--> A = [5,1,3;3,2,1;0,3,1]
A =
5 1 3
3 2 1
0 3 1
We start by calling std without a dimension argument, in
which case it defaults to the first nonsingular dimension
(in this case, along the columns or d = 1).
--> std(A)
ans =
2.5166 1.0000 1.1547
Next, we take the variance along the rows.
--> std(A,2)
ans =
2.0000
1.0000
1.5275
* FreeMat_Documentation
* Elementary_Functions
* Generated on Thu Jul 25 2013 17:17:14 for FreeMat by
doxygen_ 1.8.1.1
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