On Oct 17, 3:17 pm, [EMAIL PROTECTED] wrote: > To compute the absolute value of a negative base raised to a > fractional exponent such as: > > z = (-3)^4.5 > > you can compute the real and imaginary parts and then convert to the > polar form to get the correct value: > > real_part = ( 3^-4.5 ) * cos( -4.5 * pi ) > imag_part = ( 3^-4.5 ) * sin( -4.5 * pi ) > > |z| = sqrt( real_part^2 + imag_part^2 ) > > Is there any way to determine the correct sign of z, or perform this > calculation in another way that allows you to get the correct value of > z expressed without imaginary parts? >
Your question is not clear. (There is a cmath module if that helps). >>> z1 = complex(-3)**4.5 >>> z1 (7.7313381458154376e-014+140.29611541307906j) >>> import cmath >>> z2 = cmath.exp(4.5 * cmath.log(-3)) >>> z2 (7.7313381458154401e-014+140.29611541307909j) >>> Gerard -- http://mail.python.org/mailman/listinfo/python-list
