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How to get the modulus of a float?

General and Gameplay Programming Programming

Started by deadlydog June 18, 2005 02:23 AM

10 comments, last by Inmate2993 18 years, 10 months ago

1,729

June 18, 2005 05:28 PM

Quote:Original post by deadlydog
Quote:Original post by invective
You can also just get the decimal points like this:

float number = 1.23456
float decimal = number - (int)number;

Will (int)number always round down though?

IIRC, It will allways round to zero:

+1.8 -> +1.0
-1.8 -> -1.0

Not sure if this is "implementation dependant" (e.g. only works on x86) or if it's standard.

Inmate2993

222

June 18, 2005 07:58 PM

Modulus over real numbers. Okay.

quotient = numerator / denominator;
modulus = quotient - floor(quotient) * denominator;

5 / 3 = 1.666~
1.666~ - floor(1.666~) = .666~
.666~ * 3 = 1.999~
round(1.999~) = 2

Now, for just getting the decimal portion of a number.
modulus = number - floor(number);

all seems kinda pointless.

william bubel