L = []
x = 0
while x < 100:
x= x + 1
L= L + [x ** 2]
print (sum(L))
x = 0
while x < 100:
x= x + 1
L= L + [x ** 2]
print (sum(L))
2016-09-03
a = ['jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec']
months = set(a)
x1 = 'Feb'
x2 = 'Sun'
if x1 in months:
print 'x1: ok'
else:
print 'x1: error'
if x2 in months:
print 'x2: ok'
else:
print 'x2: error'
months = set(a)
x1 = 'Feb'
x2 = 'Sun'
if x1 in months:
print 'x1: ok'
else:
print 'x1: error'
if x2 in months:
print 'x2: ok'
else:
print 'x2: error'
2016-09-03
months = set(['1','2','3','4','5','6','7','8','9','10','11','12'])
x1 = '1'
x2 = 'asdf'
if x1 in months:
print 'x1: ok'
else:
print 'x1: error'
if x2 in months:
print 'x2: ok'
else:
print 'x2: error'
x1 = '1'
x2 = 'asdf'
if x1 in months:
print 'x1: ok'
else:
print 'x1: error'
if x2 in months:
print 'x2: ok'
else:
print 'x2: error'
2016-09-03
s = 'Python was started in 1989 by "Guido".\nPython is free and easy to learn.'
2016-09-03
ef generate_tr(name, score):
if score <60:
return '<tr><td>%s</td><td style="color:red">%s</td></tr>' % (name, score)
return '<tr><td>%s</td><td>%s</td></tr>' % (name, score)
tds = [generate_tr(name,score) for name, score in d.iteritems()]
if score <60:
return '<tr><td>%s</td><td style="color:red">%s</td></tr>' % (name, score)
return '<tr><td>%s</td><td>%s</td></tr>' % (name, score)
tds = [generate_tr(name,score) for name, score in d.iteritems()]
2016-09-03
import math
def quadratic_equation(a, b, c):
x1=(-b+math.sqrt(b*b-4*a*c))/(2.0*a)
x2=(-b-math.sqrt(b*b-4*a*c))/(2.0*a)
return x1,x2
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
def quadratic_equation(a, b, c):
x1=(-b+math.sqrt(b*b-4*a*c))/(2.0*a)
x2=(-b-math.sqrt(b*b-4*a*c))/(2.0*a)
return x1,x2
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2016-09-03
利用values来反向查询key
>>> d1={'a':1,'b':2}
>>> {value:key for key,value in d1.iteritems()}[2]
如果有重复的key
>>> d1={'a':1,'b':2,'c':1}
>>> import collections
>>> d=collections.defaultdict(list)
>>> for k,v in d1.iteritems():
... d[v].append(k)
>>> d
defaultdict(<type 'list'>, {1: ['a', 'c'], 2: ['b']})
>>> d1={'a':1,'b':2}
>>> {value:key for key,value in d1.iteritems()}[2]
如果有重复的key
>>> d1={'a':1,'b':2,'c':1}
>>> import collections
>>> d=collections.defaultdict(list)
>>> for k,v in d1.iteritems():
... d[v].append(k)
>>> d
defaultdict(<type 'list'>, {1: ['a', 'c'], 2: ['b']})
2016-09-03
def generate_tr(name, score):
if score >= 60:
return '<tr><td>%s</td><td>%s</td></tr>' % (name, score)
else:
return '<tr><td>%s</td><td style="color:red">%s</td></tr>' % (name, score)
tds = [generate_re(name, score) for name, score in d.iteritems()]
if score >= 60:
return '<tr><td>%s</td><td>%s</td></tr>' % (name, score)
else:
return '<tr><td>%s</td><td style="color:red">%s</td></tr>' % (name, score)
tds = [generate_re(name, score) for name, score in d.iteritems()]
2016-09-03
d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for k, v in d.items():
print "%s: %s" % (k, v)
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for k, v in d.items():
print "%s: %s" % (k, v)
2016-09-03
isinstance(object,class-or-type-or-tuple)--> bool ,判断一个object是否属于后面的类型～返回True或者False