nan check

NaN is an abbreviation for not a number. It is a numeric type value, typically in a floating-point calculation, that represents a value that is undefined or cannot be represented. Also, you cannot use the equality operator (= =) to check NaN. In the

1. NaN In JavaScript, NaN indicates "not a number". This value is returned when an error occurs in parsing the string:Copy codeThe Code is as follows:> Number ("xyz ")NaNNaN The name is "not a number", but it can be said that it is not a number:Copy

"NaN action is used to indicate that a value is not a number"Nan behaves strangely in JavaScript because that Nan and any value are not equal (including itself).Nan = = = Nan; FalseBecause the following code can cause some people to freak

This article mainly introduces how to judge null, undefined, and NaN in JS. If you need it, you can refer to the following str = "s" ++; Then Nan appears. Find it for a while. The collected data is judged as follows: 1. Determine undefined: The

Today in the use of MATLAB and accumulated two points, now summarized as follows 1, Objective function is undefined at the initial point. Fmincon cannot continue. Error resolution When using fmincon, this error is most likely that you solve the

In javascript, how does one determine whether a variable is null, undefined, Or NaN? Let's take a look at the specific judgment method. It is mainly determined through the typeof method. typeof returns a string and has six possible results: "number",

This article mainly introduces how to use the NaN value in JavaScript, which is the basic knowledge in JS learning, A friend may refer to the literal constant NaN without quotation marks as a special value, indicating that it is not a non-number.

This article mainly introduces how to use the NaN value in JavaScript, which is the basic knowledge in JS learning, A friend may refer to the literal constant NaN without quotation marks as a special value, indicating that it is not a non-number.

differentiate between Underfined,null and Nan Let's look at the result of the following statement: 1: var A; 2: //Show "undefined" 3: alert (typeof//Show "undefined" ) 4: alert (b); Show "Undefined" The values and types of a above are ' underfined '

1. Type analysis:JS data types have undefined,boolean,number,string,object, such as 5, the first 4 are the original type, the 5th is the reference type.CodeCode highlighting produced by Actipro Codehighlighter (freeware)