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Hello i am trying to figure out how I would easily round a double or a float to the nearest cent. It was easy enough to do it in visual basic or java, But i cannot figure out how to do it in C. I fsomebody could tell me how to do this or at least point me in the right direction it would be a great help.
Thanks,
Do you want to actually round the number in memory (hint: this is physically impossible), use an int to store integral number of pennies, or just display it with two decimal places?
How about using "round()"?
Quote:
round, roundf, roundl functions [C99]
Purpose:
Rounds a floating-point value to the nearest integer.
Syntax:
float roundf(float x);
double round(double x);
long double roundl(long double x);
Declared in:
<math.h>
Description:
The function rounds x to the nearest integer value in floating-point format, rounding halfway cases away from zero, regardless of the current rounding direction.
Returns:
The rounded integer value.
If only if only, I can't use round(unfortunately) because i am using C90 not C99 and C90 has no round function:(
Normally one uses floor or ceil for this. I prefer floor. Say if you have money = 1.455 then you can do this:
Code:double money_rounded = floor(money * 100.0 + .5) / 100.0;
I didn't realize there was a round function. Personally it always bothered me that rounding .5 to an integer is basically arbitrary. There's no reason to round either up or down.
Thanks I hope this works, to bad i cant test it until I work out the other errors in my code.