Angular - unit conversion

Question

In an Angular app, I'm showing a value in "l/h" unit, but I do a conversion to store this value in "kg/s" in my database. For example, if the user enters 30 l/h, I store 30 / 0.9506 / 3600 = 0.008766393155200223

Then, when the user refreshes the page, the value displayed is not 30 but 29.999999999999993 (the result of 0.008766393155200223 * 0.9506 * 3600).

How could I avoid this conversion side-effect?

You can't. It's a consequence of how all IEEE-754 floating-point math works. https://stackoverflow.com/questions/588004/is-floating-point-math-broken I suppose you could store the original entry, not the computed result? — , Nov 26 '19 at 18:09

score 1 · Accepted Answer · answered Nov 26 '19 at 18:30

1

As JavaScript can't handle correctly floating points, in our Angular app we have been using the 'big.js' library to deal with the the decimal operations.

Installation:

npm install big.js
npm install @types/big.js

Import:

import Big from 'big.js';

answered Nov 26 '19 at 18:30

Javi

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Perfect! you saved me :) – jcmag Nov 27 '19 at 09:00

Angular - unit conversion

1 Answers1