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Code: Alles auswählen

def set_H(self, a, b, r):
    if self.H == 0:
        r2 = (a ^ b ^ r) & 0x10
        self.H = 0 if r2 == 0 else 1

# kannst Du auch schreiben als
def set_H(self, a, b, r):
    if not self.H and ((a ^ b ^ r) & 0x10):
        self.H = 1

Code: Alles auswählen

if n>0xff:
    x = n & 0xff
else:
    x = n

Code: Alles auswählen

x = n & 0xff

Code: Alles auswählen

from timeit import Timer
import sys


# TEST_DATA = [0xff] * 10000
# TEST_DATA += [0x100] * 10000
# test1: 1.441sec
# test2: 1.434sec


TEST_DATA = [0xff] * 20000
TEST_DATA += [0x100] * 2000
# test1: 1.139sec
# test2: 1.593sec


def test1():
    for n in TEST_DATA:
        if n>0xff:
            x = n & 0xff
        else:
            x = n

def test2():
    for n in TEST_DATA:
        x = n & 0xff


if __name__ == "__main__":

    def timeit(func, number):
        name = func.__name__
        sys.stdout.write("%20s: " % name)
        sys.stdout.flush()
        t = Timer("%s()" % name, setup="from __main__ import %s" % name)
        print("%.3fsec" % t.timeit(number))

    number = 1000
    timeit(test1, number)
    timeit(test2, number)

Code: Alles auswählen

class ValueStorage8Bit(ValueStorage):
    def set(self, v):
        if v > 0xff:
            v = v & 0xff
        self.value = v
        return v # e.g.: r = operand.set(a + 1)


class ValueStorage16Bit(ValueStorage):
    def set(self, v):
        if v > 0xffff:
            v = v & 0xffff
        self.value = v
        return v # e.g.: r = operand.set(a + 1)

Code: Alles auswählen

class ValueStorage8Bit(ValueStorage):
    def set(self, v):
        v = v & 0xff
        self.value = v
        return v # e.g.: r = operand.set(a + 1)


class ValueStorage16Bit(ValueStorage):
    def set(self, v):
        v = v & 0xffff
        self.value = v
        return v # e.g.: r = operand.set(a + 1)