How do i round down float number?

Question

I have number 0.2289 and i want round down it to make 0.2200 Can i help pls ?

i tried printf(%.2f/n) but it rounds it up

I guess you could multiply it by 100.0f, then take the floorf() of that, then divide by 100.0f. — pmacfarlane, Nov 06 '22 at 21:39
Beware that while you can certainly do this, after you're done you are likely to end up with a number like 0.2199999988 or 0.22000000000000000111, because 0.22 cannot be represented exactly in binary. — Steve Summit, Nov 06 '22 at 22:02

score 0 · Answer 1 · answered Nov 06 '22 at 21:42

Usually you will not have an exact representation of the rounded number but you can try to:

double roundDown2(const double number)
{
    return floor(number * 100) / 100;
}


int main(void)
{
    printf("%.20f\n", roundDown2( 0.2289));
}

1 Answers1