March 2022
Intermediate to advanced
522 pages
13h 52m
Chinese
Content preview from Python语言及其应用（第2版）
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407
第 22章
Python
的科学
在她的统治下，
蒸汽的力量成为陆地和海洋的至尊，
现在所有人都深深依赖着
科学的新胜利。
——
James McIntyre
，
1887
年女王禧年颂歌
在过去几年间，
Python
在科学家中备受欢迎
，很大程度上是因为本章将要介绍的那些软
件。如果你是一位科学家或学生，那么可能用过像
MA
TLAB
和
R
这样的工具或者
Java
、
C
、
C++
等传统语言。现在，你将看到
Python
如何为科学分析和出版打造卓越的平台。
22.1
标准库中的数学和统计
首先，回顾一下标准库，看看我们忽视的一些特性和模块。
22.1.1
数学函数
Python
的标准
math
库汇集了大量的数学函数。只需输入
import math
就可以在程序中访问
这些函数。
其中包含一些常量，比如
pi
和
e
：
>>> import math
>>> math.pi
>>> 3.141592653589793
>>> math.e
2.718281828459045
408
｜
第
22
章
math
库主要由函数组成，下面来看看其中最实用的那些。
fabs()
会返回其参数的绝对值：
>>> math.fabs(98.6)
98.6
>>> math.fabs(-271.1)
271.1
你还可以获得数字的向下取整值（
floor()
）和向上取整值（
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