all Python 3cmathfunction

cmath.tanh()

hyperbolic functions

The hyperbolic tangent of a complex argument; for an imaginary argument tanh(i·x) = i·tan(x).

Syntax

cmath.tanh(z)

tanh(iπ/4) should be exactly 1j, but it prints 0.9999999999999999j, a typical cmath picture: an answer that is exact in mathematics differs in the last digit. So compare with cmath.isclose and round before printing. For a real x, math.tanh returns a float and needs no .real.

Examples

import cmath
z = cmath.tanh(1j * cmath.pi / 4)
print(z)  # → 0.9999999999999999j
print(cmath.isclose(z, 1j))  # → True

See also

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