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    rounding in C without math library


    Any ideas on how to go about getting a double say like 1919.1919 or anything ....and rounding it up or down accordingly?

    -gman932
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    If you cast into an integer (presuming it will fit), you will lose all the decimal places. If you then want to do your own rounding, subtract that int value from your float, then test to see if the remainder is >= 0.5 and if so, increment your int.

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    Code:
    int round (float f) {
        return (int)(f + 0.5);
    }
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    what about rounding to the fourth decimal?
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    Something like this perhaps:
    Code:
    int round2(float f, int decimals) {
        register int mult = 1;
        register int i;
        int result;
        for (i = 1; i <= decimals; i++)
            mult = mult * 10;
    
        result = ((int)(f * mult))/mult;
        return result;
    }
    Up the Irons
    What Would Jimi Do? Smash amps. Burn guitar. Take the groupies home.
    "Death Before Dishonour, my Friends!!" - Bruce D ickinson, Iron Maiden Aug 20, 2005 @ OzzFest
    Down with Sharon Osbourne

    "I wouldn't hire a butcher to fix my car. I also wouldn't hire a marketing firm to build my website." - Nilpo

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