Python cmath 模块

Python 有一个内置模块，可用于执行复数的数学任务。

该模块中的方法接受int,float，和complex数字。它甚至接受具有以下属性的 Python 对象：__complex__()或者__float__()方法。

该模块中的方法几乎总是返回一个复数。如果返回值可以表示为实数，则返回值的虚部为 0。

这个cmath模块有一组方法和常量。

数学方法

Method	Description
cmath.acos(x)	Returns the arc cosine value of x
cmath.acosh(x)	Returns the hyperbolic arc cosine of x
cmath.asin(x)	Returns the arc sine of x
cmath.asinh(x)	Returns the hyperbolic arc sine of x
cmath.atan(x)	Returns the arc tangent value of x
cmath.atanh(x)	Returns the hyperbolic arctangent value of x
cmath.cos(x)	Returns the cosine of x
cmath.cosh(x)	Returns the hyperbolic cosine of x
cmath.exp(x)	Returns the value of E^x, where E is Euler's number (approximately 2.718281...), and x is the number passed to it
cmath.isclose()	Checks whether two values are close, or not
cmath.isfinite(x)	Checks whether x is a finite number
cmath.isinf(x)	Check whether x is a positive or negative infinty
cmath.isnan(x)	Checks whether x is NaN (not a number)
cmath.log(x[, base])	Returns the logarithm of x to the base
cmath.log10(x)	Returns the base-10 logarithm of x
cmath.phase()	Return the phase of a complex number
cmath.polar()	Convert a complex number to polar coordinates
cmath.rect()	Convert polar coordinates to rectangular form
cmath.sin(x)	Returns the sine of x
cmath.sinh(x)	Returns the hyperbolic sine of x
cmath.sqrt(x)	Returns the square root of x
cmath.tan(x)	Returns the tangent of x
cmath.tanh(x)	Returns the hyperbolic tangent of x

Constant	Description
cmath.e	Returns Euler's number (2.7182...)
cmath.inf	Returns a floating-point positive infinity value
cmath.infj	Returns a complex infinity value
cmath.nan	Returns floating-point NaN (Not a Number) value
cmath.nanj	Returns coplext NaN (Not a Number) value
cmath.pi	Returns PI (3.1415...)
cmath.tau	Returns tau (6.2831...)