Скачать или смотреть How to Fix JavaScript Arithmetic Subtraction Giving Extra Unwanted Decimal Digits

Discover why `JavaScript` may produce unexpected decimal places when performing subtraction, and learn how to easily fix the issue with `toFixed()`!
---
This video is based on the question https://stackoverflow.com/q/63283209/ asked by the user 'Raj Rajeshwar Singh Rathore' ( https://stackoverflow.com/u/6178546/ ) and on the answer https://stackoverflow.com/a/63283235/ provided by the user 'Majed Badawi' ( https://stackoverflow.com/u/7486313/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: JavaScript arithmetic subtraction giving extra unwanted decimal digits

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding the Issue with JavaScript Subtraction

When working with JavaScript, you might encounter a frustrating problem: performing subtraction seems to yield more decimal places than expected. For instance, if you subtract 2 from 8.4286, instead of getting the clean result of 6.4286, you may see 6.428599999999999. This extra string of digits can confuse users and affect the integrity of data representation in your applications.

The Problem Explained

This rounding issue arises due to how computers represent decimal numbers in binary format. Here is a breakdown of the example:

[[See Video to Reveal this Text or Code Snippet]]

Actual Output:

[[See Video to Reveal this Text or Code Snippet]]

Expected Output:

[[See Video to Reveal this Text or Code Snippet]]

This unexpected behavior is a common issue in many programming languages that work with floating-point arithmetic.

Solution: Using toFixed() Method

To address this issue and ensure that your arithmetic results are presented with the desired precision, you can use the toFixed() method. This method formats a number using fixed-point notation and allows you to specify the number of digits after the decimal point.

Step-by-Step Implementation

Declare Your Variables:
First, we set our two variables for subtraction.

[[See Video to Reveal this Text or Code Snippet]]

Perform the Subtraction:
Next, we perform the subtraction and store the result in a new variable.

[[See Video to Reveal this Text or Code Snippet]]

Apply toFixed():
Use the toFixed() method to limit the result to a specific number of decimal places (in this case, 4).

[[See Video to Reveal this Text or Code Snippet]]

Output the Result:
Finally, we print the result to the console.

[[See Video to Reveal this Text or Code Snippet]]

Complete Code Example

Here’s the complete code snippet implementing the above steps:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By using toFixed(), you can easily mitigate the issue of unwanted decimal digits in your results, ensuring that your JavaScript arithmetic outputs are clean and as expected. This simple yet powerful method enhances the readability of your numerical outputs and aids in producing more reliable applications.

Now that you understand the reason for this common issue and how to fix it, you'll be able to manage your arithmetic calculations with greater confidence in the JavaScript programming environment.