math:exp

Returns the value of ex.

Signature

math:exp($arg as xs:double?) as xs:double?

Properties

This function is deterministic, context-independent, and focus-independent.

Rules

If $arg is the empty sequence, the function returns the empty sequence.

Otherwise the result is the mathematical constant e raised to the power of $arg, as defined in the [IEEE 754-2008] specification of the exp function applied to 64-bit binary floating point values.

Notes

The treatment of overflow and underflow is defined in Arithmetic operators on numeric values.

Examples

The expression math:exp(()) returns ().

The expression math:exp(0) returns 1.0e0.

The expression math:exp(1) returns 2.7182818284590455e0 (approximately).

The expression math:exp(2) returns 7.38905609893065e0.

The expression math:exp(-1) returns 0.36787944117144233e0.

The expression math:exp(math:pi()) returns 23.140692632779267e0.

The expression math:exp(xs:double('NaN')) returns xs:double('NaN').

The expression math:exp(xs:double('INF')) returns xs:double('INF').

The expression math:exp(xs:double('-INF')) returns 0.0e0.