Strange result with floating point addition

Question

Why is it when I print/display the result of

eval(\"11.05\") + eval(\"-11\")

it comes out as 0.05000000000000071 instead of the expecte

Answer 1

This has nothing to do with eval. In fact, this is what happens if you type in a console 11.05 - 11:

This is a consequence of how programming languages store floating-point numbers; they include a small error. If you want to read more about this, check this out.

Answer 2

The function eval is absolutely innocent here. The culprit is floating-point operation. If you do not expect a large number of numbers after the decimal, you may limit. But you can not avoid it.

Answer 3

This has nothing to do with eval (which you should avoid).

You get the same problem with 11.05 - 11.

This is just the usual floating point problem

Answer 4

As others have indicated, this is a floating point problem and has nothing to do with eval. Now for eval: you can easy avoid it here, using:

Number("11.05") + Number("-11");

To avoid the faulty outcome you could use toPrecision:

(Number("11.05") + Number("-11")).toPrecision(12);
// or if you want 0.05 to be the outcome
(Number("11.05") + Number("-11")).toPrecision(1);