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round-half-to-even

The value returned is the numerically closest value to

$arg

that is a multiple of ten to the power of minus

$precision

. If two such values are equally near, for example, if the fractional part in

$arg

is exactly .500..., the function returns the one whose least significant digit is even.

Syntax

fn:round-half-to-even(arg, precision)

The following table describes the argument for this command:

Argument	Required/Optional	Description
arg	Required	The number to round.
precision	Required	The precision to round the number to. It can be a positive or negative integer.

Return Value

Numeric value.

The returned value is rounded to the number of decimal places indicated by

$precision

. For example, if the precision specified is 2, the function rounds 594.3271 to 594.33. If the precision is 0, the number is rounded to an integer. Specifying a negative precision results in the number being rounded to the left of the decimal point. For example, if

$precision

is -2, the function rounds 594.3271 to 600. If

$precision

is omitted, it defaults to 0.

If the argument is exactly half way between two values, it is rounded to whichever adjacent value is even.

The result type depends the numeric type of the argument. If

$arg

is untyped, it is cast to

xs:double

Examples

The following table lists some sample values and return values:

SAMPLE FUNCTION	OUTPUT
fn:round-half-to-even(5.5)	6
fn:round-half-to-even(6.5)	6
fn:round-half-to-even(9372.253, 2)	9372.25
fn:round-half-to-even(9372.253, 0)	9372
fn:round-half-to-even(9372.253, -3)	9000