1. math相关函数
| 函 数 | 描 述 |
| ceil(x) | 大于或等于x的整数 |
| cos(x) | x的余弦 |
| degrees(x) | 将x的弧度转换为度数 |
| exp(x) | e的x次方 |
| factorial(n) | 计算n的阶乘(n!),n 必须为整数 |
| log(x) | 以e为底的x的对数 |
| log(x,b) | 以b为底的x的对数 |
| pow(x,y) | x的y次方 |
| radians(s) | 将x转换为弧度数 |
| sin(x) | x的正弦 |
| sqrt(x) | x的平方根 |
| tan(x) | x的正切 |
>>> math.ceil(1.1) 2 >>> math.cos(1) 0.5403023058681398 >>> math.degrees(1) 57.29577951308232 >>> math.exp(1) 2.718281828459045 >>> math.factorial(5) 120 >>> math.log(1) 0.0 >>> math.log(2,4) 0.5 >>> math.pow(2,3) 8.0 >>> math.sin(90) 0.8939966636005579 >>> math.sqrt(3) 1.7320508075688772 >>> math.tan(90) -1.995200412208242
2. 字符串拼接相关方法 + *
>>> 'hot' + 'dog' 'hotdog' >>> 10 * 'haha' 'hahahahahahahahahahahahahahahahahahahaha' >>> 3 * 'hee' + 2 * '!' 'heeheehee!!'
3. 列出模块中的函数 dir(module)
>>> import math >>> dir(math) ['__doc__', '__loader__', '__name__', '__package__', '__spec__', 'acos', 'acosh', 'asin', 'asinh', 'atan', 'atan2', 'atanh', 'ceil', 'copysign', 'cos', 'cosh', 'degrees', 'e', 'erf', 'erfc', 'exp', 'expm1', 'fabs', 'factorial', 'floor', 'fmod', 'frexp', 'fsum', 'gamma', 'gcd', 'hypot', 'inf', 'isclose', 'isfinite', 'isinf', 'isnan', 'ldexp', 'lgamma', 'log', 'log10', 'log1p', 'log2', 'modf', 'nan', 'pi', 'pow', 'radians', 'sin', 'sinh', 'sqrt', 'tan', 'tanh', 'trunc']
4. 查看函数的帮助字符串 help(func)
>>> help(math.floor) Help on built-in function floor in module math:floor(...)floor(x)Return the floor of x as an Integral.This is the largest integer <= x.
5. 查看文档字符串 func.__doc__
>>> print(math.floor.__doc__) floor(x)Return the floor of x as an Integral. This is the largest integer <= x.
6. 将整数和字符串转换为浮点数 float(x), x 为str 或 int类型
>>> float(3) 3.0 >>> float('3') 3.0
7. 浮点数转换为整数，int(x)舍去小数，round(x)为银行家圆整--最接近的偶数
>>> int(8.5) 8 >>> round(8.5) 8 >>> int(9.5) 9 >>> round(9.5) 10
8. 变量的多行赋值
>>> x, y, z = 1, 'two', 3.0 >>> x, y, z (1, 'two', 3.0)
