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Computing the Standard Deviation of Each Column
 Syntax `colstd(`x`)` See Also colvar , colnorm , colmax , colmean , colmad , colmse

Description
Returns the standard deviation of each column of x where x is a real, double-precision, or complex matrix. The return value is a row vector with the same number of columns as x. If x is complex, the return value is double-precision, otherwise the return value has the same type as x. The `j`th element of the return value is ```              --------------------------------------             /        _   2                    _   2            / | x   - x  |   + ... +  | x    - x  |      \    /     1,j   j                  N,j   j       \  /   ------------------------------------        \/                     N - 1 ```where `N` is the number of rows in the matrix x and ```                  N      _       1  ----      x   =  --- >     x       j      N  ----   k,j                 k = 1 ```
Example
If you enter ```      x = [{0., 2., 4.}, {0., -1., 1.}]      colstd(x) ``` O-Matrix will respond ```      [ 2 , 1 ] ```