STDDEV

Syntax | Return Value | Arguments | Keywords | Examples | Version History | See Also

The STDDEV function computes the standard deviation of an n-element vector.

Note
STDDEV uses the MOMENT function to compute the standard deviation. See MOMENT for details on how the value is calculated.

Syntax

Result = STDDEV( X [, /DOUBLE] [, /NAN] )

Return Value

The result is the standard deviation of the given vector.

Arguments

X

A numeric vector.

Keywords

DOUBLE

If this keyword is set, computations are performed in double precision arithmetic.

NAN

Set this keyword to cause the routine to check for occurrences of the IEEE floating-point values NaN or Infinity in the input data. Elements with the value NaN or Infinity are treated as missing data. (See Special Floating-Point Values (Application Programming) for more information on IEEE floating-point values.)

Examples

; Define the n-element vector of sample data:
x = [65, 63, 67, 64, 68, 62, 70, 66, 68, 67, 69, 71, 66, 65, 70]

; Compute the standard deviation:
result = STDDEV(x)

PRINT, result

IDL prints:

2.65832 

Version History

5.1

Introduced

See Also

KURTOSIS, MEAN, MEANABSDEV, MOMENT, SKEWNESS, VARIANCE