Python 简明教程

Python - math Module

Python math Module

math 模块是 Python 中用于执行数学运算的内置模块。此模块提供了用于执行不同数学任务的各种内置方法。

The math module is a built-in module in Python that is used for performing mathematical operations. This module provides various built-in methods for performing different mathematical tasks.

Note: math 模块的方法不适用于复数。为此，您可以使用 cmath 模块。

Note: The math module’s methods do not work with complex numbers. For that, you can use the cmath module.

Importing math Module

在使用 math 模块的方法之前，您需要将 math 模块导入到您的代码中。以下为语法：

Before using the methods of the math module, you need to import the math module into your code. The following is the syntax:

import math

Methods of Python math Module

以下是我们根据其功能和用法对 math 模块方法进行分类的列表。

The following is the list of math module methods that we have categorized based on their functionality and usage.

Math Module - Theoretic and Representation Methods

Python 在 math 模块中包含以下理论和表示函数 −

Python includes following theoretic and representation Functions in the math module −

Sr.No.	Function & Description
1	math.ceil(x) The ceiling of x: the smallest integer not less than x
2	math.comb(n,k) This function is used to find the returns the number of ways to choose "x" items from "y" items without repetition and without order.
3	math.copysign(x, y) This function returns a float with the magnitude (absolute value) of x but the sign of y.
4	math.cmp(x, y) This function is used to compare the values of to objects. This function is deprecated in Python3.
5	math.fabs(x) This function is used to calculate the absolute value of a given integer.
6	math.factorial(n) This function is used to find the factorial of a given integer.
7	math.floor(x) This function calculates the floor value of a given integer.
8	math.fmod(x, y) The fmod() function in math module returns same result as the "%" operator. However fmod() gives more accurate result of modulo division than modulo operator.
9	math.frexp(x) This function is used to calculate the mantissa and exponent of a given number.
10	math.fsum(iterable) This function returns the floating point sum of all numeric items in an iterable i.e. list, tuple, array.
11	*math.gcd(integers)** This function is used to calculate the greatest common divisor of all the given integers.
12	math.isclose() This function is used to determine whether two given numeric values are close to each other.
13	math.isfinite(x) This function is used to determine whether the given number is a finite number.
14	math.isinf(x) This function is used to determine whether the given value is infinity (+ve or, -ve).
15	math.isnan(x) This function is used to determine whether the given number is "NaN".
16	math.isqrt(n) This function calculates the integer square-root of the given non negative integer.
17	*math.lcm(integers)** This function is used to calculate the least common factor of the given integer arguments.
18	math.ldexp(x, i) This function returns product of first number with exponent of second number. So, ldexp(x,y) returns x2*y. This is inverse of frexp() function.
19	math.modf(x) This returns the fractional and integer parts of x in a two-item tuple.
20	math.nextafter(x, y, steps) This function returns the next floating-point value after x towards y.
21	math.perm(n, k) This function is used to calculate the permutation. It returns the number of ways to choose x items from y items without repetition and with order.
22	*math.prod(iterable, , start)** This function is used to calculate the product of all numeric items in the iterable (list, tuple) given as argument.
23	math.remainder(x,y) This function returns the remainder of x with respect to y. This is the difference x − n*y, where n is the integer closest to the quotient x / y.
24	math.trunc(x) This function returns integral part of the number, removing the fractional part. trunc() is equivalent to floor() for positive x, and equivalent to ceil() for negative x.
25	math.ulp(x) This function returns the value of the least significant bit of the float x. trunc() is equivalent to floor() for positive x, and equivalent to ceil() for negative x.

Math Module - Power and Logarithmic Methods

Sr.No.	Function & Description
1	math.cbrt(x) This function is used to calculate the cube root of a number.
2	math.exp(x) This function calculate the exponential of x: ex
3	math.exp2(x) This function returns 2 raised to power x. It is equivalent to 2**x.
4	math.expm1(x) This function returns e raised to the power x, minus 1. Here e is the base of natural logarithms.
5	math.log(x) This function calculates the natural logarithm of x, for x> 0.
6	math.log1p(x) This function returns the natural logarithm of 1+x (base e). The result is calculated in a way which is accurate for x near zero.
7	math.log2(x) This function returns the base-2 logarithm of x. This is usually more accurate than log(x, 2).
8	math.log10(x) The base-10 logarithm of x for x> 0.
9	math.pow(x, y) The value of x**y.
10	math.sqrt(x) The square root of x for x > 0

Math Module - Trigonometric Methods

Python 包含在 math 模块中执行三角计算的以下函数 −

Python includes following functions that perform trigonometric calculations in the math module −

Sr.No.	Function & Description
1	math.acos(x) This function returns the arc cosine of x, in radians.
2	math.asin(x) This function returns the arc sine of x, in radians.
3	math.atan(x) This function returns the arc tangent of x, in radians.
4	math.atan2(y, x) This function returns atan(y / x), in radians.
5	math.cos(x) This function returns the cosine of x radians.
6	math.sin(x) This function returns the sine of x radians.
7	math.tan(x) This function returns the tangent of x radians.
8	math.hypot(x, y) This function returns the Euclidean norm, sqrt(xx + yy).

Math Module - Angular conversion Methods

以下是 Python math 模块提供的角度转换函数 −

Following are the angular conversion function provided by Python math module −

Sr.No.

Function & Description

math.degrees(x) This function converts the given angle from radians to degrees.

math.radians(x) This function converts the given angle from degrees to radians.

Math Module - Mathematical Constants

Python math 模块定义了以下数学常量 −

The Python math module defines the following mathematical constants −

Sr.No.	Constants & Description
1	math.pi This represents the mathematical constant pi, which equals to "3.141592…" to available precision.
2	math.e This represents the mathematical constant e, which is equal to "2.718281…" to available precision.
3	math.tau This represents the mathematical constant Tau (denoted by τ ). It is equivalent to the ratio of circumference to radius, and is equal to 2Π.
4	math.inf This represents positive infinity. For negative infinity use "−math.inf".
5	math.nan This constant is a floating-point "not a number" (NaN) value. Its value is equivalent to the output of float('nan').

Math Module - Hyperbolic Methods

双曲函数是基于双曲线而不是圆的三角函数的类似物。以下是 Python math 模块的双曲函数 −

Hyperbolic functions are analogs of trigonometric functions that are based on hyperbolas instead of circles. Following are the hyperbolic functions of the Python math module −

Sr.No.	Function & Description
1	math.acosh(x) This function is used to calculate the inverse hyperbolic cosine of the given value.
2	math.asinh(x) This function is used to calculate the inverse hyperbolic sine of a given number.
3	math.atanh(x) This function is used to calculate the inverse hyperbolic tangent of a number.
4	math.cosh(x) This function is used to calculate the hyperbolic cosine of the given value.
5	math.sinh(x) This function is used to calculate the hyperbolic sine of a given number.
6	math.tanh(x) This function is used to calculate the hyperbolic tangent of a number.

Math Module - Special Methods

以下是 Python math 模块提供的特殊函数 −

Following are the special functions provided by the Python math module −

Sr.No.	Function & Description
1	math.erf(x) This function returns the value of the Gauss error function for the given parameter.
2	math.erfc(x) This function is the complementary for the error function. Value of erf(x) is equivalent to 1-erf(x).
3	math.gamma(x) This is used to calculate the factorial of the complex numbers. It is defined for all the complex numbers except the non-positive integers.
4	math.lgamma(x) This function is used to calculate the natural logarithm of the absolute value of the Gamma function at x.

Example Usage

以下示例演示了 math 模块及其方法的使用：

The following example demonstrates the use of math module and its methods:

# Importing math Module
import math

# Using methods of math module
print(math.sqrt(9))
print(math.pow(3, 3))
print(math.exp(1))
print(math.log(100, 10))

print(math.factorial(4))
print(math.gcd(12, 3))

Output

3.0
27.0
2.718281828459045
2.0
24
3