local complex = require "complex"complex is taken from Libraries and tools for
Lua.
complex is a math library for complex numbers based on C99.
complex library:
I __tostring(z) asinh(z) imag(z) sinh(z)
__add(z,w) __unm(z) atan(z) log(z) sqrt(z)
__div(z,w) abs(z) atanh(z) new(x,y) tan(z)
__eq(z,w) acos(z) conj(z) pow(z,w) tanh(z)
__mul(z,w) acosh(z) cos(z) proj(z) tostring(z)
__pow(z,w) arg(z) cosh(z) real(z) version
__sub(z,w) asin(z) exp(z) sin(z)