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Types of Numbers
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NumericQ
IntegerQ
MachineNumberQ
TrueQ
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Atomic Elements of Expressions
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NumberQ
NumberQ
[
expr
]
gives
True
if
expr
is a number, and
False
otherwise.
MORE INFORMATION
NumberQ
[
expr
]
returns
False
unless
expr
is manifestly a number (i.e., has head
Complex
,
Integer
,
Rational
or
Real
).
»
»
NumberQ
[
Infinity
]
gives
False
.
»
NumberQ
[
Overflow
[]]
and
NumberQ
[
Underflow
[]]
give
True
.
»
EXAMPLES
CLOSE ALL
Basic Examples
(1)
NumberQ
tests whether an object is explicitly a number:
In[1]:=
Out[1]=
In[2]:=
Out[2]=
Scope
(3)
Applications
(2)
Properties & Relations
(2)
SEE ALSO
NumericQ
IntegerQ
MachineNumberQ
TrueQ
Complexes
Assuming
TUTORIALS
Types of Numbers
Numeric Quantities
Putting Constraints on Patterns
MORE ABOUT
Atomic Elements of Expressions
Expressions
Patterns
Representation of Numbers
Testing Expressions
New in 1 | Last modified in 3
© 2008 Wolfram Research, Inc.
EXAMPLES
Basic Examples 
Scope 