pocketpy/docs/modules/cmath.md

---

icon: package

label: cmath

cmath

Complex-number arithmetic implemented in Python. Construct values with complex(real, imag=0) or imaginary literals such as 2j.

import cmath

value = complex(3, 4)
assert value.real == 3.0
assert value.imag == 4.0
assert value.conjugate() == complex(3, -4)
assert cmath.isclose(cmath.sqrt(complex(-1, 0)), complex(0, 1))
radius, angle = cmath.polar(value)
assert cmath.isclose(cmath.rect(radius, angle), value)

Group	Members
Coordinates	phase(z), polar(z), rect(radius, angle)
Powers/logarithms	exp(z), log(z, base=e), log10(z), sqrt(z)
Trigonometry	sin, cos, tan, asin, acos, atan
Hyperbolic functions	sinh, cosh, tanh, asinh, acosh, atanh
Classification	isfinite(z), isinf(z), isnan(z), isclose(a, b)
Constants	pi, e, tau, inf, infj, nan, nanj

Pass complex values explicitly to functions that access real and imag. isclose checks the real and imaginary parts with math.isclose; it does not accept CPython's tolerance keywords. Do not assume identical branch-cut or domain-error behavior for all inputs.

Implementation: cmath.py.