cmath.py 文件源码

def exp(x):
    z = _make_complex(x)

    exp_special = [
        [0+0j, None, complex(0, -0.0), 0+0j, None, 0+0j, 0+0j],
        [nan+nanj, None, None, None, None, nan+nanj, nan+nanj],
        [nan+nanj, None, 1-0j, 1+0j, None, nan+nanj, nan+nanj],
        [nan+nanj, None, 1-0j, 1+0j, None, nan+nanj, nan+nanj],
        [nan+nanj, None, None, None, None, nan+nanj, nan+nanj],
        [inf+nanj, None, complex(float("inf"), -0.0), inf, None, inf+nanj, inf+nanj],
        [nan+nanj, nan+nanj, complex(float("nan"), -0.0), nan, nan+nanj, nan+nanj, nan+nanj]
    ]

    if not isfinite(z):
        if math.isinf(z.real) and math.isfinite(z.imag) and z.imag != 0:
            if z.real > 0:
                ret = complex(math.copysign(inf, math.cos(z.imag)),
                              math.copysign(inf, math.sin(z.imag)))
            else:
                ret = complex(math.copysign(0, math.cos(z.imag)),
                              math.copysign(0, math.sin(z.imag)))
        else:
            ret = exp_special[_special_type(z.real)][_special_type(z.imag)]
        if math.isinf(z.imag) and (math.isfinite(z.real) or
                                   (math.isinf(z.real) and z.real > 0)):
            raise ValueError
        return ret

    if z.real > _LOG_LARGE_DOUBLE:
        ret = e * rect(math.exp(z.real - 1), z.imag)
    else:
        ret = rect(math.exp(z.real), z.imag)
    if math.isinf(ret.real) or math.isinf(ret.imag):
        raise OverflowError
    return ret