sum
The sum of values in a sequence
Description
The fn:sum function sums the values in a sequence. The $arg sequence can contain a mixture of numeric and untyped values. Numeric values are promoted as necessary to make them all the same type. Untyped values are cast as numeric xs:double values.
The function can also be used on duration values, so the $arg sequence can contain all xs:yearMonthDuration values or all xs:dayTimeDuration values (but not a mixture of the two).
The $zero argument allows you to specify an alternate value for the sum of the empty sequence. If $arg is the empty sequence, and $zero is provided, the function returns $zero. The $zero argument could be the empty sequence, the integer 0, the value NaN, a duration of zero seconds, or any other atomic value.
Parameters |
Description |
|---|---|
arg:numeric() |
|
zero:numeric() |
Examples
XPath |
Results |
|---|---|
sum( (1, 2, 3) ) |
6 |
7 |
|
sum($ordDoc//item/@dept) |
Error FORG0001 |
sum( (xs:yearMonthDuration(‘P1Y2M’), xs:yearMonthDuration(‘P2Y3M’)) ) |
P3Y5M |
sum( (1, 2, 3, () ) ) |
6 |
sum( (1, 2, xs:yearMonthDuration(‘P1Y’)) ) |
Error FORG0006 |
sum( () ) |
0 |
sum( (), () ) |
() |