Visual Studio 2010 que muestra un comportamiento extraño en flotación/incremento doble [duplicado]

Don't ever compare floating point values for equality unless you know exactamente what you are doing. I would strongly suggest you use integers (perhaps integer numbers of milliseconds) for this purpose.

Vea Lo que todo informático debe saber sobre la aritmética de coma flotante , para obtener más información.

Floating point is a fixed-precision format. This is an inherent limitation of fixed-precision formats.

For example, say you used six decimal digits of precision. One-third would be .333333. But if you add one-third three times, you get .999999, not 1. That's the nature of the beast.

Not exactly recommending this, but the issue is that the 0.1 cannot be represented exactly as double. 1.0 can be. So if you make your time-step a (negative) power of two, you will find a difference. By way of illustration:

    double delta = 1.0 / 8;
    int stopper = 10;
    int nextInt = 1;
    for (double t = 0; t <= stopper; t += delta)
    {
        if (t == nextInt)
        {
            std::cout << "int ";
            ++nextInt;
        }
        else 
            std::cout << "    ";
        std::cout << t << std::endl;
    }

Just round "time" after each increment to make sure it maintains a sensible value.

Algo como eso:

double round(double value, double precision)
{
    return floor(value / precision + 0.5) * precision;
}
time = round(time + 0.1, 0.1);