python学习-day02

 def capitalize(self):
""" 首字母变大写 """
def center(self, width, fillchar=None):
""" 内容居中,width:总长度;fillchar:空白处填充内容,默认无 """
def count(self, sub, start=None, end=None):
""" 子序列个数 """
def decode(self, encoding=None, errors=None):
""" 解码 """
def encode(self, encoding=None, errors=None):
""" 编码,针对unicode """
def endswith(self, suffix, start=None, end=None):
""" 是否以 xxx 结束 """
def expandtabs(self, tabsize=None):
""" 将tab转换成空格,默认一个tab转换成8个空格 """
def find(self, sub, start=None, end=None):
""" 寻找子序列位置,如果没找到,返回 -1 """
def format(*args, **kwargs): # known special case of str.format
""" 字符串格式化,动态参数,将函数式编程时细说 """
def index(self, sub, start=None, end=None):
""" 子序列位置,如果没找到,报错 """
S.index(sub [,start [,end]]) -> int
def isalnum(self):
""" 是否是字母和数字 """
"""
S.isalnum() -> bool
def isalpha(self):
""" 是否是字母 """
"""
S.isalpha() -> bool
def isdigit(self):
""" 是否是数字 """
"""
S.isdigit() -> bool
def islower(self):
""" 是否小写 """
"""
S.islower() -> bool
def isspace(self):
"""
S.isspace() -> bool
def istitle(self):
"""
S.istitle() -> bool
def isupper(self):
"""
S.isupper() -> bool def join(self, iterable):
""" 连接 """
"""
S.join(iterable) -> string
def ljust(self, width, fillchar=None):
""" 内容左对齐,右侧填充 """
"""
def lower(self):
""" 变小写 """
"""
def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
def rfind(self, sub, start=None, end=None):
"""
S.rfind(sub [,start [,end]]) -> int
def rindex(self, sub, start=None, end=None):
"""
S.rindex(sub [,start [,end]]) -> int
def rjust(self, width, fillchar=None):
"""
S.rjust(width[, fillchar]) -> string
def rpartition(self, sep):
"""
S.rpartition(sep) -> (head, sep, tail) def rsplit(self, sep=None, maxsplit=None):
"""
S.rsplit([sep [,maxsplit]]) -> list of strings
def rstrip(self, chars=None):
"""
S.rstrip([chars]) -> string or unicode
def split(self, sep=None, maxsplit=None):
""" 分割, maxsplit最多分割几次 """
"""
S.split([sep [,maxsplit]]) -> list of strings
def splitlines(self, keepends=False):
""" 根据换行分割 """
"""
S.splitlines(keepends=False) -> list of strings
def startswith(self, prefix, start=None, end=None):
""" 是否起始 """
"""
S.startswith(prefix[, start[, end]]) -> bool
def strip(self, chars=None):
""" 移除两段空白 """
"""
S.strip([chars]) -> string or unicode
def swapcase(self):
""" 大写变小写,小写变大写 """
"""
S.swapcase() -> string
def title(self):
"""
S.title() -> string
def upper(self):
"""
S.upper() -> string def zfill(self, width):
"""方法返回指定长度的字符串,原字符串右对齐,前面填充0。"""
"""
S.zfill(width) -> string

方法大全

运算符

1、算数运算:
python学习-day02
2、比较运算:
python学习-day02
3、赋值运算:
python学习-day02
4、逻辑运算:
python学习-day02

5、成员运算:

python学习-day02

基本数据类型

1、数字

int(整型)

  在32位机器上,整数的位数为32位,取值范围为-2**31~2**31-1,即-2147483648~2147483647

  在64位系统上,整数的位数为64位,取值范围为-2**63~2**63-1,即-9223372036854775808~9223372036854775807

 
查看各个数据类型的衍生功能:cmd+单击
3.1、数字
# name=("赖晓云")
# if "云1" in name:
# print("yes")
# else:
# print("no") # int # str
# isalpha() 判断字符串是否全为字母。
# name="laixi1aoyun"
# v=name.isalpha()
# print(v) #isdecimal(self):判断字符串是否全为十进制字符。
# name="123339q"
# v=name.isdecimal()
# print(v) # isdigit(self):判断字符串是否为阿拉伯数字。 # name="12331"
# v=name.isdigit()
# print(v) #isidentifier(self):判断时候为一个合法标识符,变量、函数名、数组名、文件名 # name="1aww"
# v=name.isidentifier()
# print(v) #islower(self):判断字符串时候全为小写字母。不包含大些字母 # name="1QQaww"
# v=name.islower()
# print(v) #isnumeric(self):判断字符串时候全为数字,只有数字组成。 # name="122222fa"
# v=name.isnumeric()
# print(v) #isprintable(self):是否只包含可打印字符:没有验证出false
# name="a5 @"
# v=name.isprintable()
# print(v) #isspace(self):判断字符串时候含有空格:没验证出:true # name="a来的5"
# v=name.isspace()
# print(v) #istitle(self):检测字符串中所有单词拼音首字母是否为大写,且其他字母为小写 # name="Qsasq Qdsds "
# v=name.istitle()
# print(v) # isupper(self):检测字符串包含的所有字母时候全为大写字母 # name="QQ1s"
# v=name.isupper()
# print(v) #join(self, iterable):返回通过指定字符连接序列中元素后生成的新字符串 name="+"
sqe=("a","")
v=name.join(sqe)
print(v)

int函数

3.2、布尔值

    真或假
  1 或 0
3.3、字符串
 
hello world
字符串常用功能:
  • 移除空白
  • 分割
  • 长度
  • 索引
  • 切片
str
# name=("赖晓云")
# if "云1" in name:
# print("yes")
# else:
# print("no") # int # str
# isalpha() 判断字符串是否全为字母。
# name="laixi1aoyun"
# v=name.isalpha()
# print(v) #isdecimal(self):判断字符串是否全为十进制字符。
# name="123339q"
# v=name.isdecimal()
# print(v) # isdigit(self):判断字符串是否为阿拉伯数字。 # name="12331"
# v=name.isdigit()
# print(v) #isidentifier(self):判断时候为一个合法标识符,变量、函数名、数组名、文件名 # name="1aww"
# v=name.isidentifier()
# print(v) #islower(self):判断字符串时候全为小写字母。不包含大些字母 # name="1QQaww"
# v=name.islower()
# print(v) #isnumeric(self):判断字符串时候全为数字,只有数字组成。 # name="122222fa"
# v=name.isnumeric()
# print(v) #isprintable(self):是否只包含可打印字符:没有验证出false
# name="a5 @"
# v=name.isprintable()
# print(v) #isspace(self):判断字符串时候含有空格:没验证出:true # name="a来的5"
# v=name.isspace()
# print(v) #istitle(self):检测字符串中所有单词拼音首字母是否为大写,且其他字母为小写 # name="Qsasq Qdsds "
# v=name.istitle()
# print(v) # isupper(self):检测字符串包含的所有字母时候全为大写字母 # name="QQ1s"
# v=name.isupper()
# print(v) #join(self, iterable):返回通过指定字符连接序列中元素后生成的新字符串 name="+"
sqe=("a","")
v=name.join(sqe)
print(v)

函数

3.4、列表

创建列表

 name_list = ['alex', 'seven', 'eric']
 name_list = list(['alex', 'seven', 'eric'])

基本操作:

  • 索引
  • 切片
  • 追加
  • 删除
  • 长度
  • 切片
  • 循环
  • 包含
dd

list函数

5、元祖
创建元祖:
ages = (1122334455)
ages = tuple((1122334455))
基本操作:
  • 索引
  • 切片
  • 循环
  • 长度
  • 包含
lass tuple(object):
"""
tuple() -> empty tuple
tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object.
"""
def count(self, value): # real signature unknown; restored from __doc__
""" T.count(value) -> integer -- return number of occurrences of value """
return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
T.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
return 0 def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass def __contains__(self, y): # real signature unknown; restored from __doc__
""" x.__contains__(y) <==> y in x """
pass def __eq__(self, y): # real signature unknown; restored from __doc__
""" x.__eq__(y) <==> x==y """
pass def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y): # real signature unknown; restored from __doc__
""" x.__getitem__(y) <==> x[y] """
pass def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__
"""
x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported.
"""
pass def __ge__(self, y): # real signature unknown; restored from __doc__
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y): # real signature unknown; restored from __doc__
""" x.__gt__(y) <==> x>y """
pass def __hash__(self): # real signature unknown; restored from __doc__
""" x.__hash__() <==> hash(x) """
pass def __init__(self, seq=()): # known special case of tuple.__init__
"""
tuple() -> empty tuple
tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object.
# (copied from class doc)
"""
pass def __iter__(self): # real signature unknown; restored from __doc__
""" x.__iter__() <==> iter(x) """
pass def __len__(self): # real signature unknown; restored from __doc__
""" x.__len__() <==> len(x) """
pass def __le__(self, y): # real signature unknown; restored from __doc__
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y): # real signature unknown; restored from __doc__
""" x.__lt__(y) <==> x<y """
pass def __mul__(self, n): # real signature unknown; restored from __doc__
""" x.__mul__(n) <==> x*n """
pass @staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y): # real signature unknown; restored from __doc__
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass def __rmul__(self, n): # real signature unknown; restored from __doc__
""" x.__rmul__(n) <==> n*x """
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" T.__sizeof__() -- size of T in memory, in bytes """
pass tuple

6、字典(无序)
创建字典: 
 person = {"name": "mr.wu", 'age': 18}

person = dict({"name": "mr.wu", 'age': 18}) 
class dict(object):
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list. For example: dict(one=1, two=2)
""" def clear(self): # real signature unknown; restored from __doc__
""" 清除内容 """
""" D.clear() -> None. Remove all items from D. """
pass def copy(self): # real signature unknown; restored from __doc__
""" 浅拷贝 """
""" D.copy() -> a shallow copy of D """
pass @staticmethod # known case
def fromkeys(S, v=None): # real signature unknown; restored from __doc__
"""
dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
v defaults to None.
"""
pass def get(self, k, d=None): # real signature unknown; restored from __doc__
""" 根据key获取值,d是默认值 """
""" D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """
pass def has_key(self, k): # real signature unknown; restored from __doc__
""" 是否有key """
""" D.has_key(k) -> True if D has a key k, else False """
return False def items(self): # real signature unknown; restored from __doc__
""" 所有项的列表形式 """
""" D.items() -> list of D's (key, value) pairs, as 2-tuples """
return [] def iteritems(self): # real signature unknown; restored from __doc__
""" 项可迭代 """
""" D.iteritems() -> an iterator over the (key, value) items of D """
pass def iterkeys(self): # real signature unknown; restored from __doc__
""" key可迭代 """
""" D.iterkeys() -> an iterator over the keys of D """
pass def itervalues(self): # real signature unknown; restored from __doc__
""" value可迭代 """
""" D.itervalues() -> an iterator over the values of D """
pass def keys(self): # real signature unknown; restored from __doc__
""" 所有的key列表 """
""" D.keys() -> list of D's keys """
return [] def pop(self, k, d=None): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
If key is not found, d is returned if given, otherwise KeyError is raised
"""
pass def popitem(self): # real signature unknown; restored from __doc__
""" 获取并在字典中移除 """
"""
D.popitem() -> (k, v), remove and return some (key, value) pair as a
2-tuple; but raise KeyError if D is empty.
"""
pass def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
""" 如果key不存在,则创建,如果存在,则返回已存在的值且不修改 """
""" D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
pass def update(self, E=None, **F): # known special case of dict.update
""" 更新
{'name':'alex', 'age': 18000}
[('name','sbsbsb'),]
"""
"""
D.update([E, ]**F) -> None. Update D from dict/iterable E and F.
If E present and has a .keys() method, does: for k in E: D[k] = E[k]
If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v
In either case, this is followed by: for k in F: D[k] = F[k]
"""
pass def values(self): # real signature unknown; restored from __doc__
""" 所有的值 """
""" D.values() -> list of D's values """
return [] def viewitems(self): # real signature unknown; restored from __doc__
""" 所有项,只是将内容保存至view对象中 """
""" D.viewitems() -> a set-like object providing a view on D's items """
pass def viewkeys(self): # real signature unknown; restored from __doc__
""" D.viewkeys() -> a set-like object providing a view on D's keys """
pass def viewvalues(self): # real signature unknown; restored from __doc__
""" D.viewvalues() -> an object providing a view on D's values """
pass def __cmp__(self, y): # real signature unknown; restored from __doc__
""" x.__cmp__(y) <==> cmp(x,y) """
pass def __contains__(self, k): # real signature unknown; restored from __doc__
""" D.__contains__(k) -> True if D has a key k, else False """
return False def __delitem__(self, y): # real signature unknown; restored from __doc__
""" x.__delitem__(y) <==> del x[y] """
pass def __eq__(self, y): # real signature unknown; restored from __doc__
""" x.__eq__(y) <==> x==y """
pass def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass def __getitem__(self, y): # real signature unknown; restored from __doc__
""" x.__getitem__(y) <==> x[y] """
pass def __ge__(self, y): # real signature unknown; restored from __doc__
""" x.__ge__(y) <==> x>=y """
pass def __gt__(self, y): # real signature unknown; restored from __doc__
""" x.__gt__(y) <==> x>y """
pass def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list. For example: dict(one=1, two=2)
# (copied from class doc)
"""
pass def __iter__(self): # real signature unknown; restored from __doc__
""" x.__iter__() <==> iter(x) """
pass def __len__(self): # real signature unknown; restored from __doc__
""" x.__len__() <==> len(x) """
pass def __le__(self, y): # real signature unknown; restored from __doc__
""" x.__le__(y) <==> x<=y """
pass def __lt__(self, y): # real signature unknown; restored from __doc__
""" x.__lt__(y) <==> x<y """
pass @staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass def __ne__(self, y): # real signature unknown; restored from __doc__
""" x.__ne__(y) <==> x!=y """
pass def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__
""" x.__setitem__(i, y) <==> x[i]=y """
pass def __sizeof__(self): # real signature unknown; restored from __doc__
""" D.__sizeof__() -> size of D in memory, in bytes """
pass __hash__ = None dict

dict

PS:循环,range,continue 和 break

 

其他

用户按照顺序循环可迭代对象中的内容,
PS:break、continue
 
1、for循环
用户按照顺序循环可迭代对象中的内容,
PS:break、continue
li = [11,22,33,44]
for item in li:
print item

  

2、enumrate
为可迭代的对象添加序号
 li = [11,22,33]
for k,v in enumerate(li, 1):
print(k,v)
3、range和xrange
指定范围,生成指定的数字
print range(110)
# 结果:[1, 2, 3, 4, 5, 6, 7, 8, 9]
 
print range(1102)
# 结果:[1, 3, 5, 7, 9]
 
print range(300-2)
# 结果:[30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2]  
 

练习题

 

一、元素分类

有如下值集合 [11,22,33,44,55,66,77,88,99,90...],将所有大于 66 的值保存至字典的第一个key中,将小于 66 的值保存至第二个key的值中。

即: {'k1': 大于66的所有值, 'k2': 小于66的所有值}

二、查找
查找列表中元素,移除每个元素的空格,并查找以 a或A开头 并且以 c 结尾的所有元素。
    li = ["alec", " aric", "Alex", "Tony", "rain"]
    tu = ("alec", " aric", "Alex", "Tony", "rain") 
    dic = {'k1': "alex", 'k2': ' aric',  "k3": "Alex", "k4": "Tony"}
 
三、输出商品列表,用户输入序号,显示用户选中的商品
    商品 li = ["手机", "电脑", '鼠标垫', '游艇']
 
四、购物车

功能要求:

  • 要求用户输入总资产,例如:2000
  • 显示商品列表,让用户根据序号选择商品,加入购物车
  • 购买,如果商品总额大于总资产,提示账户余额不足,否则,购买成功。
  • 附加:可充值、某商品移除购物车
goods = [
{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998},
]

 五、用户交互,显示省市县三级联动的选择

dic = {
"河北": {
"石家庄": ["鹿泉", "藁城", "元氏"],
"邯郸": ["永年", "涉县", "磁县"],
}
"河南": {
...
}
"山西": {
...
} }
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