# **math** – 数学函数

!!! tip "简介"
    `math` 模块提供了对 C 标准定义的数学函数的访问。 
    
    **注意** : 需要带有硬件FPU，精度是32位，这个模块需要浮点功能支持。

## 函数

- math.acos(x)  
  返回 ``x`` 的反余弦。

- math.acosh(x)  
  返回 ``x`` 的逆双曲余弦。

- math.asin(x)  
  返回 ``x`` 的反正弦。

- math.asinh(x)  
  返回``x`` 的逆双曲正弦。

- math.atan(x)  
  返回 ``x`` 的逆切线。

- math.atan2(y, x)  
  Return the principal value of the inverse tangent of y/x.

- math.atanh(x)  
  Return the inverse hyperbolic tangent of x.

- math.ceil(x)  
  Return an integer, being x rounded towards positive infinity.

- math.copysign(x, y)  
  Return x with the sign of y.

- math.cos(x)  
  Return the cosine of x.

- math.cosh(x)  
  Return the hyperbolic cosine of x.

- math.degrees(x)  
  Return radians x converted to degrees.

- math.erf(x)  
  Return the error function of x.

- math.erfc(x)  
  Return the complementary error function of x.

- math.exp(x)  
  Return the exponential of x.

- math.expm1(x)  
  Return exp(x) - 1.

- math.fabs(x)  
  Return the absolute value of x.

- math.floor(x)  
  Return an integer, being x rounded towards negative infinity.

- math.fmod(x, y)  
  Return the remainder of x/y.

- math.frexp(x)  
  Decomposes a floating-point number into its mantissa and exponent. The returned value is the tuple (m, e) such that x == m * 2**e exactly. If x == 0 then the function returns (0.0, 0), otherwise the relation 0.5 <= abs(m) < 1 holds.

- math.gamma(x)  
  Return the gamma function of x.

- math.isfinite(x)  
  Return True if x is finite.

- math.isinf(x)  
  Return True if x is infinite.

- math.isnan(x)  
  Return True if x is not-a-number

- math.ldexp(x, exp)  
  Return x * (2**exp).

- math.lgamma(x)  
  Return the natural logarithm of the gamma function of x.

- math.log(x)  
  Return the natural logarithm of x.

- math.log10(x)  
  Return the base-10 logarithm of x.

- math.log2(x)  
  Return the base-2 logarithm of x.

- math.modf(x)  
  Return a tuple of two floats, being the fractional and integral parts of x. Both return values have the same sign as x.

- math.pow(x, y)  
  Returns x to the power of y.

- math.radians(x)  
  Return degrees x converted to radians.

- math.sin(x)  
  Return the sine of x.

- math.sinh(x)  
  Return the hyperbolic sine of x.

- math.sqrt(x)  
  Return the square root of x.

- math.tan(x)  
  Return the tangent of x.

- math.tanh(x)  
  Return the hyperbolic tangent of x.

- math.trunc(x)  
  返回一个整数, x 接近于0。

## 常数

- math.e  
  自然对数的底

- math.pi  
  圆周率
  
更多内容可参考  [math](https://docs.python.org/3.5/library/math.html?highlight=math#module-math) 。

----------