Rounding calculations

[lynxbci]

Hi,

I have a formula that peforms a calculation, and as the inputs are double, the calc is too.

private double calcpoints(float input_pr, float input_ca, float input_fa, float input_fi) {
		return ((input_pr / 10.9) + (input_ca / 9.2) + (input_fa / 3.9) + (input_fi / 35));

However, this return 7.8443242 and i want it to return 8 (rounded value)
How do i do this please?

thanks

[Fabken]

Hello Lynxbci, there is a round method in the java.lang.math library.

Fabrice

[Fabken]

float test = (float) 2.45;
long testRound= Math.round(test);

this is how you use it.

[lynxbci]

Thanks very much all working ok

[RPFeltz]

Perhaps converting it to an int value works too.
double test = 7.82562;
int rounded = (int) test;

[R-J]

Perhaps converting it to an int value works too.
double test = 7.82562;
int rounded = (int) test;

That will round everything between a 7 and an 8 to a 7.

[RPFeltz]

What about this:
double test = 7.82562;
int rounded = (int) (test + 0.5);

[R-J]

That works unless the number is negative.

[sunde887]

In general it's better to use what the libraries provide for you. Casting to an integer simply truncates the decimal portion. Like rj said, if x is -.6 and you did (int)(x+.5) you will still get 0.

[Fubarable]

Or perhaps better would be to not round at all, but format the output into a nicely formatted and rounded String representation when this is needed. This can easily be done with a DecimalFormat object or String.format(...) method call.