IsInteger

Tests whether x is manifestly an integer.

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

IsInteger(x)True if x is an integer, False otherwise

Typed signatures

Type	Package	Applies
(any) -> boolean	combinatorics	always

Domain: Collections

Details

• Returns False unless x is provably an integer -- there's no third "unknown" outcome, same convention as IsPrime.
• A free symbol, or anything compute-engine can't classify, answers False.

Examples

Basic #

live ↗

In$\mathrm{IsInteger}(4)$Out$\mathrm{True}$

Unknown $x$ cannot be shown integral, so the answer is False

live ↗

In$\mathrm{IsInteger}(x+4)$Out$\mathrm{False}$

Scope #

live ↗

In$\mathrm{IsInteger}(\frac{1}{2})$Out$\mathrm{False}$

live ↗

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

live ↗

In$\mathrm{IsInteger}(-3)$Out$\mathrm{True}$

About

Examples	5
Checked against	Wolfram Language 5 agree
Crosswalk	Wolfram Language

See also: IsPrime, IsTrue