Python数据类型

a=10
b=0
b+=a
c=-100
c-=a
print (a, b ,c)
print (dir(a))
print (abs(a)+abs(c))
print type(a)

a = 3.0
b = 2.5
c = 2.4
print (round(a))
print (round(b))
print (round(c))
print ('##' * 20)
c = 2.555
d = 1.545
print (round(c,2))
print (round(d,2))

print (not True)
a = 10
b = 20
c = 100
print (not (a>b and c>a))

a = 'abcdef'
b = 'bbbbb'
c = 'ccccc'
print (dir(a))
print (a,b,c)
print (type(a))
print (a[0], a[1], a[2])

print (a.find('d'))

print (a.replace('a','h'))

b = 'asdaaaadfgaaadfghjaaa'
print (b.split('aaa'))

print ('333'.join(a))
print ('333'.join(b.split('aaa')))

把字符串取出来后左右空格去掉
s = '  ll  jj   ddd   '
print s
print (s.strip())
print (s.lstrip())
print (s.rstrip())

name = 'adfgfdfdg'
print ('hello' +name)
f = '{0},{1},{0}'.format('aa',name)
print f
g = ('my name is %s') % 'alex'
print g
print ('{name}:{age}'.format(name='alex',age=27))

a = ['a','b','c',1,'abc']
print a
print type(a)
print dir(a)

a.append('hell0')
print a

print a.index('abc')

a.insert(3,'abcxb')
print a

a.pop()
print a

a.remove(1)
print a

a.sort()
print a

a.reverse()
print a

print (a[0:4])
print (a[1:3:2])

t = 'aswrtgbvfg'
print t
print (tuple(t))
a = ('a','b','c',123,'a','a')
print a
print type(a)
m = ('a',)
print type(m)
print (dir(a))

print a.count('a')

print a.index('b')

k= {'name':'alex','age':'20'}
print k
print type(k)
k1 = dict(a = 1,b=2,c=3)
d=dict([('name','alex'),('age',27)])
print d
print k1
print dir(k1)

print k1.clear()

print k.get('name')

print (k.setdefault('address','shanghai'))

print (k.keys())
print (k.iterkeys())
print (k.values())

print(k.iteritems())
for x,y in k.iteritems():
    print (x,y)

print (k.items())
print k
print '#'*20

print (k.pop('address'))
print k

v= ['a','b','c','d']
m = {}
n = m.fromkeys(v,123)
b = dict.fromkeys(v,123)
print n

a1 = ['a','b','c','d']
a2 = [1,2,3,4]
a3 = zip(a1,a2)
print a3
print k
print k1

k1.update(k)
print k1
k2 = dict(a=1,b=10,c=7,d=2)
print k2

print sorted(k2.items())

a = 1
help(sorted)
dir(a)
#int str dict list tuple
age = 20
print('My age is:' +str(age))