var
- var(fs)
Computes the point-wise variance in
fs
.The output is a
Fieldset
with one field only. A missing value in any field infs
will result in a missing value in the corresponding grid point in the output fieldset.With n fields in
fs
by denoting the i-th value in the k-th field by \(x_{i}^{k}\) the output values can be written as:\[v_{i} = \frac {1}{n} \sum_{k}^{n} (x_{i}^{k})^2 - (\frac {1}{n} \sum_{k}^{n} x_{i}^{k})^2\]Note
The following lines are equivalent:
y = mv.var(x) y = mv.mean(x*x)-mv.mean(x)**2