how long is double

From: f (ffunus_at_yahoo.com)
Date: 01/04/04

  • Next message: Derek Baker: "Re: [OT] ACCU website" 
    Date: 3 Jan 2004 21:26:11 -0500

    I have this

    double sum, a, b, c;
    sum = a + b + c;
    printf("%.20f = %.20f, %.20f, %.20f", sum, a, b, c);

    I found that the debug version and release version of the same code
    give me different result. I am using VC++ 6.0.

    In debug version, the print out is:
    -12.25938471938358500000 = -11.43596388399630500000,
    -0.07591666113607631300, -0.74750417425120252000,

    In the release version, the print out is:
    -12.25938471938358300000 = -11.43596388399630500000,
    -0.07591666113607631300, -0.74750417425120252000,

    The above sum = a + b + c is just a part of my computation. I found
    that my whole computation crushed in the debug version because some
    number became zero and another number divide this number. But this did
    not happened in the release version.

    Why?

    Thanks,

    ff

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  • Next message: Derek Baker: "Re: [OT] ACCU website"

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