What is NaN ?
NaN, acronym for “Not a Number” is an exception which usually occurs in the cases when an expression results in a number that can’t be represented. For example square root of negative numbers.
How to check for NaN ?
Method 1 : Using compare (“==”) operator.
In this method we check if a number is complex by comparing it with itself. If the result is true, then the number is not complex i.e., real. But if result is false, then “nan” is returned, i.e the number is complex.
Its a real number Its NaN
Method 2 : Using inbuilt function “isnan()”.
Another way to check for NaN is by using “isnan()” function, this function returns true if a number is complex else it returns false.
Its a real number Its NaN
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