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noninteger

A noninteger is a real number that is not an integer. In set terms, it is any element of the real numbers R that does not belong to the integers Z. Equivalently, a real number x is a noninteger if its fractional part is nonzero, or if floor(x) ≠ x. Nonintegers include all numbers with a nonzero fractional part, whether positive or negative.

Nonintegers can be divided into rational and irrational categories. Some are rational, such as 1/2, 3.5, and

Key properties include that nonintegers are dense in the real numbers: between any two real numbers there

−7.25,
which
can
be
expressed
as
a
ratio
of
integers.
Others
are
irrational,
such
as
√2,
π,
and
e,
which
cannot
be
written
as
a
simple
fraction
and
have
nonrepeating,
non-terminating
decimal
representations.
The
set
of
nonintegers
comprises
both
these
types
and
excludes
only
the
whole
numbers
like
...,
−2,
−1,
0,
1,
2,
...
exist
infinitely
many
nonintegers.
They
form
a
large,
non-discrete
subset
of
R,
in
contrast
to
the
integers,
which
are
discrete.
The
concept
is
common
in
mathematics
and
in
computing,
where
noninteger
values
correspond
to
fractional
or
floating-point
numbers
as
opposed
to
whole-number
integers.
This
distinction
underpins
rounding,
truncation,
and
flooring
operations,
and
it
is
relevant
in
measurements,
statistics,
and
numerical
analysis.