JS calculations (not DFFS)

[Maciek Grischke]

I noticed a strange behaviour when calculating in JS.

One user submitted a form today with the following values:

var one = 14.8;
var two = 7.4;
var three = 29.6;
var four = 5;
var total = one+two+three+four;

The result is: 56.800000000000004 instead of 56.8.

I know I can use match.round, but I’d like to understand what is actually happening.
I saw similar behaviour in Microsoft Flow.

This seems to be happening when .2 increments are used.

[Alexander Bautz]

Hi,
This is how JavaScript handles floating point numbers – you find some more info here, but it’s quite complicated (and it’s way over my head…) – the simple solution is to use .toFixed(2) to truncate the number to two decimals.

Alexander

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