Name
NaN — the not-a-number property
Availability
JavaScript 1.3; JScript 3.0; ECMAScript v1
Synopsis
NaN
Description
NaN
is global property that refers to the special
numeric not-a-number value. The NaN
property is
not enumerated by for/in
loops and cannot be
deleted with the delete
operator. Note that
NaN
is not a constant and can be set to any other
value, something that you should take care not to do.
To determine if a value is not a number, use isNaN( )
, since NaN
always compares non-equal
to any other value, including itself!
See Also
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