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Python cmath - tan() Function

The Python cmath.tan() function returns complex tangent of a complex number z. It is a function on complex plane, and has no branch cuts. It is periodic with respect to the real component, with period 𝜋j, and has poles of the first order along the real line, at coordinates (𝜋(1/2 + n), 0). However no common floating-point representation is able to represent 𝜋/2 exactly.

Mathematically, it can be expressed as:

complex tan




z Required. Specify the complex number, representing an angle expressed in radians.

Return Value

Returns the complex tangent of z.


In the example below, tan() function is used to find out the complex tangent of the given number.

import cmath

z1 = 2 + 2j
z2 = 2
z3 = 2j

print("cmath.tan(z1):", cmath.tan(z1))
print("cmath.tan(z2):", cmath.tan(z2))
print("cmath.tan(z3):", cmath.tan(z3))

The output of the above code will be:

cmath.tan(z1): (-0.028392952868232294+1.0238355945704727j)
cmath.tan(z2): (-2.185039863261519+0j)
cmath.tan(z3): 0.9640275800758169j

❮ Python cMath Module