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Rocket Alpaca
7,318 PointsparseInt(.5) vs parseInt(".5")
Why is it that only the string runs into an error of NAN?
2 Answers
Nicholas Hebb
18,872 PointsIt's kind of a two step answer.
parseInt() expects a string for the parameter. When you run parseInt(.5), it automatically converts the non-string .5 into the string "0.5". (Note the leading zero).
When parseInt runs, it expects the first character of the string to be numeric. So "55 cows" will parse to 55, but "cows 55" will return NaN.
Therefore, since ".5" starts with a decimal point instead of a number, it returns NaN. Do it again as parseInt("0.5") and you'll get the same result as parseInt(.5).
sjbrown0324
13,995 PointsNaN means 'Not a Number'. A string is not a number. .5 without quotes is a number. .5 with quotes is a string.
Rocket Alpaca
7,318 PointsRocket Alpaca
7,318 PointsThat makes sense, thanks!
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 PointsAakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 PointsHey Nicholas . I run the code as you mentioned :
1 is giving "NaN" as output but 2 is giving 0 as output.