How to convert string(float) into number without adding exponential (e)

Question

I'm trying to convert string into number but it is adding exponential symbol. I'm expecting the same output but in number not in string.

I have tried toFixed(), but it is returning string.

For example

var x = "0.00000001";
+x.toFixed(8);
console.log(x); // Actual Output: "0.00000001" | Expected output: 0.00000001

Sample code
var x = "0.00000001";
+x; // output: 1e-8

Actual Output: "0.00000001"

Expected output: 0.00000001

that is just how JavaScript expresses large (as in lots of digits) numbers. it's still just a plain old number. you can do math with it or convert it back to a string to view it in long form. — I wrestled a bear once., Aug 26 '19 at 12:39
`0.00000001` *is* `1e-8`. It's literally the same value. If you need the value formatted for display, then use a string, if you want to use mathematical operations, then it doesn't matter how JS formats the numeric value. — VLAZ, Aug 26 '19 at 12:40

Wiimm · Answer 1 · 2019-09-03T04:42:43.780

1

If you print a number without formatting, the javascript interpeter decides the format. It tries to select a short format with respect to the precision. So 0.00000001 is printed as 1e-8.

Code analysis:

var x = "0.00000001";

Here yo assign a string to x.

+x.toFixed(8);

This should throw an error for the part x.toFixed(8), because toFixed() is not defined for string. Maybe you wanted:

(+x).toFixed(8);

The plus sign converts the string into a number, and then toFixed(8) creates a formatted string for that number. The result is not used in any way (expect console output).

console.log(x);

In the line before, you didn't changed the value of x. So it's still the assigned string of the first line and you get the correct "0.00000001"

edited Sep 03 '19 at 04:42

answered Aug 27 '19 at 14:15

Wiimm

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Your result is same as input, which is wrong because this will again returns the string not the number. – Harsh Gupta Aug 28 '19 at 07:31
Do you read my comment especially the last sentence? You assigned a string to x, don't modify x and print x. So the output of x is still a string. And the debugging (!) function `console.log()` reflects the string type by quotes. If you assign x to a input element like `input.value = x` the input box don't show the quotes. – Wiimm Aug 29 '19 at 13:19

score -1 · Answer 2 · answered Aug 26 '19 at 12:45

-1

try this

  var oldString = '0.00000001';
  var oldNumber = Number('0.00000001');
   const str = oldNumber.toString();

    const exponent = parseInt(str.split('-')[1], 10);
    const result = oldNumber.toFixed(exponent);
    console.log(result);

answered Aug 26 '19 at 12:45

ANIK ISLAM SHOJIB

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How does this "fix" the problem? `oldNumber` is still represented as `1e-8`. The OP already knows how to use `toFixed` to get a string representation. – Heretic Monkey Aug 26 '19 at 12:47
Old Number doesn't but result does it is explained here follow them for better explanations https://stackoverflow.com/questions/1458633/how-to-deal-with-floating-point-number-precision-in-javascript – ANIK ISLAM SHOJIB Aug 26 '19 at 12:51
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Answers should be self-contained; I should be able to understand your answer and how it relates to the question without visiting another question. Also, that question has nothing to do with this one; it's about floating point accuracy when doing mathematical operations. This one demonstrates a lack of understanding of how numbers are stored in JavaScript. – Heretic Monkey Aug 26 '19 at 12:55
sorry for the inconvenience I will get back to you soon – ANIK ISLAM SHOJIB Aug 26 '19 at 13:12
I have already tried `.toFixed()` and the problem is it will return output string datatype but I need number datatype. – Harsh Gupta Aug 28 '19 at 11:54

How to convert string(float) into number without adding exponential (e)

2 Answers2