nanvar
statistics: v = nanvar (x)
statistics: v = nanvar (x, w)
statistics: v = nanvar (x, w, 'all')
statistics: v = nanvar (x, w, dim)
statistics: v = nanvar (x, w, vecdim)
Compute the variance while ignoring NaN values.
v = nanvar (x) returns the variance of x, after
removing NaN values. If x is a vector, a scalar value is
returned. If x is a matrix, a row vector of column variances is
returned. If x is a multidimensional array, nanvar operates
along the first nonsingleton dimension. If a dimension contains fewer than
two non-NaN values, the variance is returned as 0 for a single value
and as NaN when all values are NaN.
v = nanvar (x, w) specifies the normalization. When
w is 0 (default), the variance is normalized by , where
is the number of non-NaN observations. When w is 1,
it is normalized by . w may also be a vector of nonnegative
weights whose length matches the operating dimension, in which case the
weighted variance normalized by the sum of the weights is returned.
v = nanvar (x, w, returns the
variance of all elements of x, after removing 'all')NaN values. Use
an empty value, w = [], to pass the default normalization.
v = nanvar (x, w, dim) operates along the
dimension dim of x.
v = nanvar (x, w, vecdim) returns the variance
over the dimensions specified in the vector vecdim. A weight vector is
not supported together with 'all' or vecdim. Any dimension in
vecdim greater than ndims (x) is ignored.
See also: var, nanstd, nanmean, nansum
Source Code: nanvar
Find the column variances for a matrix with missing values.
x = magic (3); x([1, 6:9]) = NaN
x =
NaN 1 NaN
3 5 NaN
4 NaN NaN
v = nanvar (x)
v = 0.5000 8.0000 NaN
Find the row variances, normalized by N instead of N-1.
x = magic (3); x([1, 6:9]) = NaN
x =
NaN 1 NaN
3 5 NaN
4 NaN NaN
v = nanvar (x, 1, 2)
v = 0 1 0