Python TutorialFor Beginners

对 2015-11-20

http://pqx.ee/

Intro 时

Python /ˈpaɪθɑːn/ in us

or /ˈpaɪθən/ in uk

Created By Guido van Rossum

in 1989- 1989 快以可⽣生起 快 “ ”

- ABC 快 ⼤大perl lisp

-

Monty Python's Flying Circus

BBC 来

Features and philosophy

• 了 了 • 了 中⼀一 了 • ( ) • 著 • ( & )

Language Features

• Beautiful is better than ugly • Explicit is better than implicit • Simple is better than complex • Complex is better than complicated • Readability counts

The Zen of Python

there should be one and preferably only one obvious way to do it

快

• 和 • 发好

batteries included

快

• GUI • •

为过成

“ ⾃自” “ 上” “ ”

Use

• Web Web

• Scipy Numpy

• 有 (google TensorFlow)

• GUI PyQT wxWorks

• ( perl bash)

•

Python 也

Python

Raspberry Pi python GPIO Pi python

quick start

Installation /

• brew install python

• apt-get install python

• yum install python

• … also, binary Installer for Windows

Hello World

print “hello world”

• Just as simple as

Interrupter / 能

能 evaluate

能

有

有能

* python

能

能

run python code /

$ python helloWorld.py

• python 有

• CPython • IPython

• PyPy

• IronPyton

• Jython

run python code / • REPL 也

$ python

Python 2.7.10 (default, Jul 14 2015, 19:46:27)

[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.39)] on darwin

Type "help", "copyright", "credits" or "license" for more information.

>>> print "hello world"

hello world

(Read-Eval-Print Loop)

Mathematics /

+, -, *, /, //, %, **

出 (3.5 ) @

==, >, <, >=, <=, != and, or, not

=, +=, -=, *=, /=, %=

variables /

x = 1

x = ‘hello world!’

• 了 快

•

• 好

Mathematics / • (++) 不(--)

x = 3

x += 1

x -= 2

indentation /

if x >= 60:

print ‘passed!’

else:

print ‘failed!’

• { } python

• 快 • • 没

多• ...

comments /

# comments in single line

•

•'''comments in multi line

line 2

line 3

'''

conditions /

if x >= 90:

print ‘A’

elif x >= 75:

print ‘B’

elif x >= 60:

print ‘C’

else:

print ‘D’

• if else elif

conditions /

switch !!!

成if... elif... elif... else

loops /

x = 0

while(x<100):

x = 1

print x

• while

loops /

for i in range(100):

print i

• for..in..

loops / • continue break (c java )x = 0

while True:

x = x + 1

if x > 100:

break

loops / • while for..in..

• do..while

• until

• goto

data structures

numbers /

• int• float

• complex

str /

• 好

• % format

•

list /

•

• 的

• (List comprehensions)

dict / 都( )

•

• 的

tuple / 个• 快 都 key

• list ,

• 新

set / 是

• 新 list

>>> set([1, 2, 3, 4, 1, 2])

set([1, 2, 3, 4])

bool /

• True / False

• python :

None

• False

•

• int• float• complex

Mutable Immutable

• str

• list• set• dict

• tuple

•

functions

function / • 快 None

def square(x):

return x*x

• 要 快 快

def pow(x, y=2):

return x**y

好 在• 好 在

pow(y=3, x=2)

• *

def square_sum(*values):

s = 0

for i in values:

s += i*i

return s

( )• * *

def print_values(**values):

for k in values:

print ‘%s => %s’ % (k, values[k])

class and objects 了

class / 了 好

class Animal():

def __init__(self, name):

self.name = name

def sayHi(self):

print self.name, 'says Hi!'

builtin method / 要• __init__ • __del__ • __repr__ • __str__ • __unicode__

• 会

•__x _classname__x

class Cat(Animal):

def __init__(self, name='kitty'):

self.name = name

def sayHi(self):

print ‘hello %s mio!’ % self.name

了

•了

•

• 1+2 (1).__add__(2)

•

module and import

module /

• 最

• sys.modules

开 开 PYTHONPATH 开 要

import /

• 快

• (__import__)

• execfile

input and output 下 下

IO

• raw_input (python3 input)

• sys.stdin sys.stdout

• print

• open

• read

• write

json

• dumps

• loads

advanced features

• lambda ( )

•

• map reduce filter

•

—

• dir hasattr getattr setattr

• eval exec

• locals globals

要

• 成 __doc__ __name__ __file__

• : __dict__ __class__

•了: __doc__ __module__ __dict__ __bases__

• yield 有

• 有

• 了

• C/C++ 分 python

summary

• 了 了 • 了 中⼀一 了 • ( ) • 著 • ( & )

Features /

https://github.com/vinta/awesome-python

去 C

JAVA C#

Python !!!