Name
isnan, isinf, isfinite, isnormal, signbit — IEEE 754 floating-point classification functions
Synopsis
isnan(
|
in x double precision); |
signbit(
|
in x double precision); |
isinf(
|
in x double precision); |
isfinite(
|
in x double precision); |
isnormal(
|
in x double precision); |
Description
These functions classify an IEEE 754 double precision floating point
value. Each returns an integer 1 if the predicate holds for
x, 0 otherwise.
: isnan 1 if x is a NaN (Not-a-Number), 0 otherwise.
: isinf 1 if x is positive or negative infinity, 0 otherwise.
: isfinite 1 if x is neither infinity nor NaN, 0 otherwise.
: isnormal 1 if x is a normal (non-zero, non-subnormal, non-infinity, non-NaN) value.
: signbit 1 if the IEEE 754 sign bit of x is set (i.e. x is negative, including -0.0), 0 otherwise.
See also
isfinitenumeric
for the SQL-level check that combines type and finite-value testing across
any numeric type.
Return Types
integer (0 or 1).
Examples
Example 24.125. Simple Examples
SQL> select isnan (0.0/0.0), isinf (1.0/0.0), isfinite (1.0), isnormal (1e-310);