SUM Function

Sums an array of n dimensions over one of its dimensions.

result = SUM (array, dim)

array An array of n dimensions of any data type except string.

dim The dimension over which array is summed. The dim parameter must be a number in the range 0 dim (n-1), where n is the number of dimensions in array.

result A scalar value equal to the sum of the array elements over the specified dimension.

None.

If array is either a single or double-precision complex, or a double-precision floating-point data type, the result is of the same data type. SUM returns a single-precision floating-point value for all other acceptable data types.

This example illustrates SUM being used for a variety of arrays of different sizes.

array1 = FINDGEN(2)
array2 = FINDGEN(2,2)

; Create two arrays, array1, a one-dimensional array with two 

; elements and array2, a two-dimensional array with four elements,

; using FINDGEN.

PRINT, array1

0.00000      1.00000

PRINT, array2

0.00000      1.00000
2.00000      3.00000

PRINT, SUM(array1, 0)

1.00000

PRINT, SUM(array2, 0)

1.00000      5.00000

PRINT, SUM(array2, 1)

2.00000      4.00000

; Print the arrays then sum each array over each of its dimensions

; and print the result.

AVG, MAX, MEDIAN, MIN, STDEV, TOTAL