THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
SEE THE DOCUMENTATION CENTER FOR THE LATEST INFORMATION.

DOCUMENTATION CENTER SEARCH

Mathematica > Core Language > Expressions > Testing Expressions > IntegerQ >

Mathematica > Core Language > Procedural Programming > Conditionals > Testing Expressions > IntegerQ >

IntegerQ

IntegerQ[expr]
gives True if expr is an integer, and False otherwise.

IntegerQ[expr] returns False unless expr is manifestly an integer (i.e. has head Integer).

Simplify[exprIntegers] can be used to try to determine whether an expression is mathematically equal to an integer.

IntegerQ tests whether an expression is explicitly an integer:

Out[1]=

Out[2]=

Test whether an array consists of all integers:

Make a test for Gaussian integers:

Integers have head Integer:

An expression may have head Integer, but IntegerQ gives False:

Expressions that do not evaluate to integers explicitly will still give False:

It is necessary to use symbolic simplification first: