std2计算矩阵元素的标准差；mean2计算矩阵元素的平均数。

help std2

STD2 Compute standard deviation of matrix elements.

B = STD2(A) computes the standard deviation of the values in

A.

Class Support

-------------

A can be numeric or logical. B is a scalar of class double.

Example

-------

I = imread('liftingbody.png');

val = std2(I)

See also corr2, mean2, mean, std.

Reference page in Help browser

doc std2

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help mean2

MEAN2 Compute mean of matrix elements.

B = MEAN2(A) computes the mean of the values in A.

Class Support

-------------

A can be numeric or logical. B is a scalar of class double.

Example

-------

I = imread('liftingbody.png');

val = mean2(I)

See also mean, std, std2.

Reference page in Help browser

doc mean2