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学习网站:
教程:
http://woodpecker.org.cn/abyteofpython_cn/chinese/
python学习
http://www.ibm.com/developerworks/cn/linux/theme/python/
用python写监控(glances)
https://github.com/nicolargo/glances
GAE:
http://www.appifan.com/jc/201209/35517.html
ubuntu自带python,版本为2.7
sn@sn:~/script$ python
Python 2.7.5+ (default, Sep 19 2013, 13:48:49)
[GCC 4.8.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 3+4
7
>>> 100*12
1200
>>> help
Type help() for interactive help, or help(object) for help about object.
>>> print("Welcome to python")
Welcome to python
>>> print "Python is fun"
Python is fun
##########
() :函数
# :单行注释
"" :字符串
''' ''':多行注释
>>> print(3+4*4)
19
>>> print(3 + 4 * 4)
19
######计算圆的面积
vim test.py
r = eval(input("Enter a value for radius:"))
area = r * r * 3.14
print "r is:",r," area is:",area
//执行
python test.py
###
标识符:
(1)字母、数字、_
(2)不能是以数字开头
(3)不能使用关键字
(4)可以任意长度
####
i=k=l=3
一个变量必须先初始化
>>> a,b,c=1,2,3
>>> print a
1
>>> print b
2
>>> print c
3
##交换ab的值
>>> a,b=b,a
>>> print a
2
>>> print b
1
##输入多个值
>>> n1,n2,n3 = eval(input("values:"))
values:"1,2,3"
>>> a=(n1+n2+n3)/3
>>> print(a);
2
###
/ :代表不整除
//:代表整除
###
取整
>>> value =6.7
>>> print value
6.7
>>> value =int(value)
>>> print value
6
四舍五入
>>> value1 = 8.9
>>> print(round(value1))
9.0
>>> print(value1)
8.9
abs(x):绝对值
min()
max()
round(x,n):小数点后保留n位
""与''都代表字符串
改变类型
s = str(3.4)
s="ss"
print(s.lower())
strip
for i in range(1,10):
for var in [1,2,3]:
function:
def max(n1,n2):
if n1>n2:
result = n1
else:
result = n2
return result
large =max(3,2)
print(large)
##变量
globalvar = 1
def f1():
localvar = 2
globalvar = 3
print(globalvar)
print(localvar)
f1()
print(globalvar)
#print(localvar)
x = 1
def increase():
global x
x = x + 1
print(x)
increase()
print(x)
##参数的默认值
def printArea(w =1, h =2):
area = w * h
print "w:", w , "h:", h ," area:" , area
printArea()
printArea(3,5)
printArea(h=5,w=3)
printArea(h=5)
printArea(w=3)
###
def sort(n1,n2):
if n1 < n2:
return n1,n2
else:
return n2,n1
n1, n2 = sort(8, 4)
print("n1 is",n1)
print("n2 is",n2)
###
>>> a = "qwert"
>>> len(a)
5
>>> max(a)
'w'
>>> min(a)
'e'
===
>>> a="HELLO"
>>> print(a[1])
E
>>> print(a[1:3])
EL
>>> print(a[1:4])
ELL
>>> print(a[:4])
HELL
>>> print(a[3:])
LO
>>> print(a[1:-1])
ELL
>>> print(a[:])
HELLO
====
>>> s1 = "Welcome "
>>> s2 = 3*s1
>>> print s2
Welcome Welcome Welcome
===
>>> s1 = "Welcome"
>>> print("come" in s1)
True
>>> print("come" not in s1)
False
===比较的是
>>> print("green" == "glow")
False
>>> print("green" != "glow")
True
>>> print("green" > "glow")
True
>>> print("green" >= "glow")
True
>>> print("green" < "glow")
False
>>> print("green" <= "glow")
False
>>> print("ab" <= "abc")
True
>>> print("az" <= "azzz")
True
>>> print("az" >= "azzz")
False
==遍历字符串
s = "Welcome"
for ch in s:
print(ch)
==
s = "welcome to python"
print(s.isalnum()) --是否有数字
print(s.islower()) --是否都是小写
print(s.isupper()) --是否都是大写
print(s.isspace()) --是否为空格
print("Welcome".isalpha()) --全部都是字母
print("2012".isdigit()) --全部都是数字
print("first number".isidentifier()) --该方法在2.7没有
print(s.endswith("thon")) --以thon结尾
print(s.startswith("good")) --以good开头
print(s.find("come")) --come开始的下标
print(s.find("become")) --没有这个则为-1
---
>>> s = "welcome to python come"
>>> print(s.rfind("come"))
18
>>> print(s.find("come"))
3
s1 = s.capitalize() --s的首字母大写
print(s1)
s2 = s.title() --s的所有单词首字母都大写
print(s2)
s = "New England"
s3 = s.lower() --s的所有字母都小写
print(s3)
s4 = s.upper() --s的所有字母都大写
print(s4)
s5 = s.swapcase() --s的所有首字母都小写,其它字母大写
print(s5)
s6 = s.replace("England", "Haven") --把s中的"England"替换为"Haven"
print(s6)
print(s) --注意原来的s不会改变
print(s.rfind("o")) --s中最后一个"o"的下标
print(s.count("o")) --s中"o"的个数
s = " Welcome to Python\t"
s1 = s.lstrip() --去掉首的空格
print(s1)
s2 = s.rstrip() --去掉尾的空格
print(s2)
s3 = s.strip() --去掉行首和尾的空格
print(s3)
s = "Welcome"
s1 = s.center(11) --剧中,长度11
print(s1)
s2 = s.ljust(11) --居左,长度11
print(s2)
s3 = s.rjust(11) --居右,长度11
print(s3)
s4 = s.format(11)
<<<
####
list []
list [2,1,3]
list ["kk","ll"]
list [1,"aa"]
import random
random.shuffle(list)
print(list)
append(x: object) 在最后增加x
>>> list = [2,3,4,1,4]
>>> list.append(5)
>>> print(list)
[2, 3, 4, 1, 4, 5]
>>> print(list.count(4)) ---4的下标
2
>>> list2 = [99,52]
>>> list.extend(list2)
>>> print(list)
[2, 3, 4, 1, 4, 5, 99, 52]
>>> print(list.index(4))
2
>>> list.insert(1,25) --下标为1的位置加25
>>> print(list)
[2, 25, 3, 4, 1, 4, 5, 99, 52]
>>> print(list.pop(2)) --下标为2的元素
3
>>> print(list.pop()) --最后一个
52
>>> list.remove(1) --移除元素
>>> print(list)
[2, 25, 4, 4, 5, 99]
>>> list.reverse() --换位置,首尾
>>> print(list)
[5, 4, 4, 25]
>>> list.sort() --排序
>>> print(list)
[4, 5, 25]
>>> list = [1,2,3]
>>> list2 = [3,4,5]
>>> list3 = list +list2
>>> print(list3)
[1, 2, 3, 3, 4, 5]
>>> list = [1,2,3]
>>> list2 = 3*list
>>> print(list2)
[1, 2, 3, 1, 2, 3, 1, 2, 3]
sets 不能重复
字典:
####files
def main():
outfile = open("a.txt", "w")
outfile.write("Hello")
outfile.write("World\n")
outfile.write("Python")
outfile.close
main()
python test7.py
出现一个a.txt的文件
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