IsNumeric

Whether expr denotes a definite numeric quantity, without evaluating it.

✓ checked against that system · ! checked, with disagreements (hover a chip)Wolfram LanguageNumericQ✓↗

IsNumeric(expr)$True$ for a number literal or an expression built from numeric literals and constants like $\pi$, $False$ otherwise.

Typed signatures

Type	Package	Applies
(any) -> boolean	combinatorics	always

Domain: Collections

Details

• Wolfram spells this NumericQ; renamed to the Is… convention used across compute-engine predicates.
• A plain symbol with no numeric value (like x) is not numeric, even though it could later be assigned one.

Examples

Basic #

live ↗

In$\mathrm{IsNumeric}(π)$Out$\mathrm{True}$

live ↗

In$\mathrm{IsNumeric}(5)$Out$\mathrm{True}$

$\sin\sqrt2$ is a constant, so it counts as numeric

live ↗

In$\mathrm{IsNumeric}(\sin(\sqrt{2}))$Out$\mathrm{True}$

Scope #

A plain symbol carries no definite numeric value

live ↗

In$\mathrm{IsNumeric}(x)$Out$\mathrm{False}$

Built from numeric literals and a known numeric function

live ↗

In$\mathrm{IsNumeric}(\sqrt{2})$Out$\mathrm{True}$

A free symbol is not numeric

live ↗

In$\mathrm{IsNumeric}(\mathrm{expr})$Out$\mathrm{False}$

live ↗

In$\mathrm{IsNumeric}(k)$Out$\mathrm{False}$

About

Examples	7
Checked against	Wolfram Language 7 agree
Crosswalk	Wolfram Language

See also: IsMachineNumber, Precision