How to round float value?

[Steve]

I have float value, let say 123.456789. How can I round it to two decimal
digits after decimal point?

For example:

123.456789 -> 123.45

It should be some simple way ...

Thanks

[Mihajlo Cvetanoviæ]

Steve wrote:

I have float value, let say 123.456789. How can I round it to two decimal
digits after decimal point?

For example:

123.456789 -> 123.45

You should use double, it's more precise:

#include <math.h>
....
double f = 123.456789;
double r1 = floor(f * 100) / 100;
double r2 = floor(f * 100 + 0.5) / 100;

r1 is 123.45, which is 123.456 "floored" to two decimal digits.
r2 is 123.46, which is 123.456 rounded to two decimal digits.

If you really need to work with floats use floorf().

[Mihajlo Cvetanoviæ]

Steve wrote:

I have float value, let say 123.456789. How can I round it to two decimal
digits after decimal point?

For example:

123.456789 -> 123.45

You should use double, it's more precise:

#include <math.h>
....
double f = 123.456789;
double r1 = floor(f * 100) / 100;
double r2 = floor(f * 100 + 0.5) / 100;

r1 is 123.45, which is 123.456 "floored" to two decimal digits.
r2 is 123.46, which is 123.456 rounded to two decimal digits.

If you really need to work with floats use floorf().