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product

Computes the product of the input.

Prototype

	function product (
		x  : numeric   
	)

	return_val [1] :  typeof(x)

Arguments

x

An array of any dimensionality.

Return value

A scalar value of the same type as x

Description

Returns the product of the input values, regardless of dimensionality. It ignores missing values.

See Also

dim_product, avg, sum, stddev

Examples

Example 1

Calculate the number of elements (ne) in an array. Let x(120,5,73,144), then use dimsizes to get the size of each dimension: 

  ne   = product( dimsizes(x)) ; ===> 120*5*73*144 = 6307200
Example 2

In the example below, see how setting the missing value, x@_FillValue, changes the product calculation: 

  x    = (/ (/1,-99/), (/3,4/), (/-99,6/) /)
  xproduct = product(x)
;
; Before missing value is set, xproduct = 705672.
;
  print(xproduct)

  x@_FillValue = -99
  xproduct = product(x)
;
; After missing value is set, xproduct = 72.
;
  print(xproduct)