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stddev

Calculates the sample standard deviation.

Prototype

```	function stddev (
data  : numeric
)

return_val  :  float or double
```

Arguments

data

A 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))
```

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:   
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:   
Coordinates:
(0)     43.44537

```