mo_moment::variance Interface Reference

Standard deviation of a vector. More...

Public Member Functions
real(sp) function	variance_sp (dat, mask)
real(dp) function	variance_dp (dat, mask)

Detailed Description

Standard deviation of a vector.

Calculates the sample variance of a vector, i.e. the second moment

\[\sigma_x^2 = \sum_i\frac{(x_i-\bar x)^2}{N-1}\]

If an optional mask is given, the average is only over those locations that correspond to true values in the mask. \(x\) can be single or double precision. The result will have the same numerical precision.

Parameters

[in]	real(sp/dp) :: dat(:)	1D-array with input numbers.
[in]	logical, optional :: mask(:)	1D-array of logical values with size(dat). If present, only those locations in vec corresponding to the true values in mask are used.

Return values

real(sp/dp) :: variance

Sample variance of all elements in dat.

Note

Input values must be floating points.
This is the sample variance. The population variance is: var = variance * (n-1)/n

Author

Matthias Cuntz

Date

Nov 2011

Definition at line 604 of file mo_moment.f90.

Member Function/Subroutine Documentation

variance_dp()

real(dp) function mo_moment::variance::variance_dp	(	real(dp), dimension(:), intent(in)	dat,
		logical, dimension(:), intent(in), optional	mask
	)

Definition at line 1673 of file mo_moment.f90.

variance_sp()

real(sp) function mo_moment::variance::variance_sp	(	real(sp), dimension(:), intent(in)	dat,
		logical, dimension(:), intent(in), optional	mask
	)

Definition at line 1709 of file mo_moment.f90.

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The documentation for this interface was generated from the following file:

• src/mo_moment.f90