math module official document: https://docs.python.org/3/library/math.html
The math module functions can be divided according to the purposes comprising: number theory and represents a function, a power function and logarithmic functions, trigonometric functions, angle conversion, hyperbolic functions, specific functions and constants
The math module comprising a part of the function of the most commonly used functions as follows :( been identified in red)
| Number theory and representation functions |
| function | Features |
|---|---|
| ceil(x) | Of the floating point number x is rounded up, i.e. the smallest integer greater than or equal to x, returns integer value |
| floor(x) | Of the floating point number x rounded down, i.e., less than or equal to the maximum integer x, integer value return |
| copysign (x, y) | x and y values returned to the same number, a floating point type |
| fabs(x) | The absolute value of the number of x, and the floating point |
| factorial(x) | X number of requirements x!, i.e. factorial of x, returns the integer |
| fmod(x, y) | Seeking x/yremainder of fmod()the %similar, except that, fmodin order xto determine the sign of the remainder, %in order yto determine the sign of the remainder |
| frexp(x) | Returns a tuple consisting of a mantissa and exponent x is (m,e)calculated: x is divided by 0.5 and 1, to give a range of values 2 E value to be within this range, e is the greatest integer meet the requirements, x / 2 e obtain m values if x is equal to 0, the value of m and e are 0, the absolute value of m ranges from (0.5) between 0.5 and 1 are not included |
| fsum(iterable) | Iterator for each element in the sum the operation and return to floating point |
| gcd(x, y) | Greatest common divisor integers x and y, gcd(0, 0)returns 0 |
| isclose(a, b, *, rel_tol=1e-09, abs_tol=0.0) | If the values of a and b is relatively close returns True, otherwise Falserel_tol: maximum relative tolerance, is the maximum allowed difference between a and b, such as to set a tolerance of 5%, the rel_tol=0.05 default tolerance to 1e-09ensure that the two values in approximately the same nine decimal digits. rel_tolIt must be greater than zero abs_tol: the minimum absolute tolerance: For close to zero useful. abs_tolMust be at least zero if no error occurs, the result will be: abs(a-b) <= max(rel_tol * max(abs(a), abs(b)), abs_tol) |
| isfinite(x) | If x is not infinite, it is returned True, otherwise False(note 0.0 is considered to be limited) |
| isinf(x) | If x is positive infinity or negative infinity is returned True, otherwiseFalse |
| isnan(x) | If x is not a number, the return True, otherwise returnFalse |
| ldexp(x, i) | Return * X (2 I ) value. It is a function of frexp()inverse function |
| modf(x) | Back tuple x integer part and a fractional part composed of |
| remainder(x, y) | IEEE 754 style return x modulo y with respect to x and limited finite nonzero y, which is the difference x - n * y, where n is an integer closest to the exact value of the quotient of x / y if x / y is located just between two integers, then the nearest integer for n * even * remainder r = remainder (x, y) therefore always satisfy abs (r) <= 0.5 * abs (y) a special case follows the IEEE 754: in particular, remainder (x, math.inf) for any finite x x is the remainder (x, 0) and the remainder (math.inf, x) raise a ValueError applies to any of NaN x If the result of the modulo operation is zero, then the x zero will have the same sign in the use of IEEE 754 binary floating-point platform, the result of this operation can always be fully represented: do not introduce rounding errors |
| trunc(x) | X rounding floating-point numbers (fractional part discarded), returns the integer value trunc(x)function-with //similar results divisible, except that the trunc(x)value returned by the shaping function, the //value returned is divisible float |
| Power function and logarithmic function |
| function | Features |
|---|---|
| exp(x) | Return e x , e to the power x times, where e = 2.718281 ... is the natural logarithm base, which is usually higher than Math.E x more accurate or pow (math.e, x) |
| expm1(x) | Returns e x -1, i.e. power minus x-e 1, e = 2.718281 ... which is the base of natural logarithm |
| log(x[, base]) | 返回 x 的自然对数，默认以 e 为基数，base 参数给定时，将 x 的对数返回给定的 base，计算式为：log(x)/log(base) |
| log1p(x) | 返回 x+1 的自然对数 (基数为e) 的值 |
| log2(x) | 返回 x 以 2 为底的对数，通常比 log(x, 2) 更准确 |
| log10(x) | 返回 x 底为10的对数，通常比 log(x, 10) 更准确 |
| pow(x, y) | 返回 x 的 y 次幂，即 xy |
| sqrt(x) | 返回 x 的平方根 |
| 三角函数 |
| 函数 | 功能 |
|---|---|
| cos(x) | 返回 x 弧度的余弦值 |
| sin(x) | 返回 x 弧度的正弦值 |
| tan(x) | 返回 x 弧度的正切值 |
| acos(x) | 以弧度为单位返回 x 的反余弦值 |
| asin(x) | 以弧度为单位返回 x 的反正弦值 |
| atan(x) | 以弧度为单位返回 x 的反正切值 |
| atan2(y, x) | 以弧度为单位返回 atan(y / x) ，结果在 -pi 和 pi 之间 从原点到点 (x, y) 的平面矢量使该角度与正X轴成正比 atan2() 的点的两个输入的符号都是已知的，因此它可以计算角度的正确象限 例如， atan(1) 和 atan2(1, 1) 都是 pi/4 ，但 atan2(-1, -1) 是 -3*pi/4 |
| hypot(x, y) | 返回欧几里德范数，sqrt(x*x + y*y) ，这是从原点到点 (x, y) 的向量长度 |
| 角度转换 |
| 函数 | 功能 |
|---|---|
| degrees(x) | 将角度 x 从弧度转换为度数 |
| radians(x) | 将角度 x 从度数转换为弧度 |
| 双曲函数（基于双曲线而非圆来对三角函数进行模拟） |
| 函数 | 功能 |
|---|---|
| acosh(x) | 返回 x 的反双曲余弦值 |
| asinh(x) | 返回 x 的反双曲正弦值 |
| atanh(x) | 返回 x 的反双曲正切值 |
| cosh(x) | 返回 x 的双曲余弦值 |
| sinh(x) | 返回 x 的双曲正弦值 |
| tanh(x) | 返回 x 的双曲正切值 |
| 特殊函数 |
| 函数 | 功能 |
|---|---|
| erf(x) | 可用于计算传统的统计函数，如 累积标准正态分布 |
| erfc(x) | 返回 x 处的互补误差函数。 互补错误函数 定义为 1.0 - erf(x)。 它用于 x 的大值，从其中减去一个会导致 有效位数损失 |
| gamma(x) | 返回 x 处的 伽马函数值 |
| lgamma(x) | 返回 Gamma 函数在 x 绝对值的自然对数 |
| 常量 |
| 函数 | 功能 |
|---|---|
| math.pi | 数学常数 π = 3.141592…，精确到可用精度 |
| math.e | 数学常数 e = 2.718281…，精确到可用精度 |
| math.tau | 数学常数 τ = 6.283185…，精确到可用精度，Tau 是一个圆周常数，等于 2π，圆的周长与半径之比 |
| math.inf | 浮点正无穷大（对于负无穷大，使用 -math.inf ）相当于 float('inf') 的输出 |
| math.nan | 浮点非数字（NaN）值，相当于 float('nan') 的输出 |
