What does nan mean in js

NaN means "not a number" in JavaScript and is generated in the following situations: non-number when converting a string to a number, valueless arithmetic operation, NaN arithmetic operation. NaN cannot be compared normally, so you need to use the Number.isNaN() function. NaN is often used to handle data that cannot be represented as numbers, allowing the program to give a reasonable response when encountering invalid data.

What is NaN

NaN stands for "Not a Number" (Not a Number) in JavaScript and is a A special value used to represent situations that cannot be represented as numbers.

Generated Scenarios

NaN is usually produced in the following situations:

• When trying to convert a non-numeric string to a number, e.g. "abc".
• Attempt to perform an arithmetic operation on an operand that has no value, such as 0/0.
• Perform arithmetic operations using NaN values ​​as input values.

Comparing NaN

NaN cannot be compared to any other value using the regular comparison operators (== or ===). Any comparison with NaN always returns false.

To do this, the Number.isNaN() function should be used, which accepts a parameter and returns a Boolean value indicating whether the parameter is NaN.

Operations on NaN

The result of arithmetic operations on NaN is usually NaN unless compared to a number. For example:

• NaN 10 = NaN
• NaN * 3 = NaN
• NaN > 0 = false
• NaN === NaN = false

Uses of NaN

NaN is useful for working with data that cannot be represented as numbers. It allows a program to respond appropriately when it encounters invalid data, such as displaying an error message or returning a default value.

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