1.math简介
>>>import math #导入math模块 >>>dir(math) #这句可查看所有函数名列表 >>>help(math) #查看具体定义及函数原型
2.常用函数
acos(x) # Return the arc cosine (measured in radians) of x.
asin(x) # Return the arc sine (measured in radians) of x.
atan(x) # Return the arc tangent (measured in radians) of x.
atan2(y, x) # Return the arc tangent (measured in radians) of y/x.
# Unlike atan(y/x), the signs of both x and y are considered.
ceil(x) # Return the ceiling of x as a float.
# This is the smallest integral value >= x.
cos(x) # Return the cosine of x (measured in radians).
cosh(x) # Return the hyperbolic(双曲线的) cosine of x.
degrees(x) # converts angle x from radians(弧度) to degrees
exp(x) # Return e raised to the power of x.
fabs(x) # Return the absolute value of the float x.
floor(x) # Return the floor of x as a float.
# This is the largest integral value <= x.
fmod(x,y) # Return fmod(x, y), according to platform C. x % y may differ.
frexp(x) # Return the mantissa and exponent of x, as pair (m, e).
# m is a float and e is an int, such that x = m * 2.**e.
# If x is 0, m and e are both 0. Else 0.5 <= abs(m) < 1.0.
hypot(x,y) # Return the Euclidean distance, sqrt(x*x + y*y).
ldexp(x, i) # x * (2**i)
log(x[, base]) # the logarithm of x to the given base.
# If the base not specified, returns the natural logarithm (base e) of x.
log10(x) # the base 10 logarithm of x.
modf(x) # Return the fractional and integer parts of x. Both results carry the sign
# of x. The integer part is returned as a real.
pow(x,y) # Return x**y (x to the power of y).
radians(x) # converts angle x from degrees to radians
sin(x) # Return the sine of x (measured in radians).
sinh(x) # Return the hyperbolic sine of x.
sqrt(x) # Return the square root of x.
tan(x) # Return the tangent of x (measured in radians).
tanh(x) # Return the hyperbolic tangent of x.
另外该模块定义了两个常量:
e = 2.7182818284590451 pi = 3.1415926535897931
