Returns the non-negative square root of the argument.
math:sqrt
( $arg
as xs:double?
xs:double?
If $arg
is the empty sequence, the function returns the empty sequence.
Otherwise the result is the mathematical non-negative square root of $arg
as defined in the specification of the
squareRoot
function applied to 64-bit binary floating point values.
The expression math:sqrt(())
returns ()
.
The expression math:sqrt(0.0e0)
returns 0.0e0
.
The expression math:sqrt(-0.0e0)
returns -0.0e0
.
The expression math:sqrt(1.0e6)
returns 1.0e3
.
The expression math:sqrt(2.0e0)
returns 1.4142135623730951e0
.
The expression math:sqrt(-2.0e0)
returns xs:double('NaN')
.
The expression math:sqrt(xs:double('NaN'))
returns xs:double('NaN')
.
The expression math:sqrt(xs:double('INF'))
returns xs:double('INF')
.
The expression math:sqrt(xs:double('-INF'))
returns xs:double('NaN')
.
The treatment of the invalidOperation
exception is defined in . The effect is that if the argument is less than zero, the result
is NaN
.
If $arg
is positive or negative zero, positive infinity, or
NaN
, then the result is $arg
. (Negative zero is the only
case where the result can have negative sign)