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stddev
Calculates the sample standard deviation.
Prototype
function stddev ( data : numeric ) return_val [1] : float or double
Arguments
dataA numeric array of any dimensionality.
Return value
The return value will be a scalar of type double if data is double, and a scalar of type float otherwise.
Description
This function returns the sample standard deviation of the input data, regardless of dimensionality. Missing values (data@_FillValue) are ignored. To determine the number of data points used to calculate the standard deviation, use:
N = num(.not.ismissing(data))
See Also
Examples
Example 1
The following calculates the sample standard deviation of 5 values.
f = (/ 7, 9, -2, -8, 2/) std_f = stddev(f) print(std_f) Variable: std_f Type: float Total Size: 4 bytes 1 values Number of Dimensions: 1 Dimensions and sizes: [1] Coordinates: (0) 6.8775
Example 2
The following calculates the sample standard deviation of a (3,5,10) array, f.
f = onedtond(ispan(1, 150, 1), (/3, 5, 10/)) stddev_f = stddev(f) print(stddev_f) Variable: stddev_f Type: float Total Size: 4 bytes 1 values Number of Dimensions: 1 Dimensions and sizes: [1] Coordinates: (0) 43.44537