通常的经验是,在Android设备中,浮点数会比整型慢两倍,在缺少FPU和JIT的G1上对比有FPU和JIT的Nexus One中确实如此(两种设备间算术运算的绝对速度差大约是10倍)
This is true on a FPU-less, JIT-less G1 and a Nexus One with an FPU and the JIT. (Of course, absolute speed difference between those two devices is about 10x for arithmetic operations.)
它直接把小数点后面的数值丢弃掉了,因为,凭直觉,那些整型数和结果应该是一个浮点数据,但是我需要一个更精确的数值。
It just throws the decimal point away and that's because, again, these are ints and the answer intuitively should be a floating point value, but I need to be more specific.
浮点数和小数不象整数一样“循规蹈矩”,不能假定浮点计算一定产生整型或精确的结果,虽然它们的确“应该”那样做。
Floating point and decimal Numbers are not nearly as well-behaved as integers, and you cannot assume that floating point calculations that "should" have integer or exact results actually do.
It just throws the decimal point away and that's because, again, these are ints and the answer intuitively should be a floating point value, but I need to be more specific.
它直接把小数点后面的数值丢弃掉了,因为,凭直觉,那些整型数和结果应该是一个浮点数据,但是我需要一个更精确的数值。
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