d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59, 'Paul': 74 }
sum = 0.0
for ave in d.items():
sum += ave[1]
print ave[0], ':', ave[1]
print 'average',':',sum/len(d)
正常
但是
sum = 0,0
for key,value in d.items():
sum =sum + value
print key,':',value
print 'average',':',sum/len(d)
确实不可以的，不太明白
sum = 0.0
for ave in d.items():
sum += ave[1]
print ave[0], ':', ave[1]
print 'average',':',sum/len(d)
正常
但是
sum = 0,0
for key,value in d.items():
sum =sum + value
print key,':',value
print 'average',':',sum/len(d)
确实不可以的，不太明白
2016-09-16
s = set(['Adam', 'Lisa', 'Paul'])
L = ['Adam', 'Lisa', 'Bart', 'Paul']
s.add('Bart')
s.remove('Adam')
s.remove('Lisa')
s.remove('Paul')
print s
L = ['Adam', 'Lisa', 'Bart', 'Paul']
s.add('Bart')
s.remove('Adam')
s.remove('Lisa')
s.remove('Paul')
print s
2016-09-16
已采纳回答 / Jason__Wang
The method pop() removes and returns last object or obj from the list.The method insert() inserts object obj into list at offset index.所以这句代码的意思是把L的最后一个数据放到最前边来。
2016-09-16
def firstCharUpper(s):
return s[0:1].upper()+s[1:]
print firstCharUpper('hello')
print firstCharUpper('sunday')
print firstCharUpper('september')
return s[0:1].upper()+s[1:]
print firstCharUpper('hello')
print firstCharUpper('sunday')
print firstCharUpper('september')
2016-09-15
d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59 }
def geneTr(name, score):
style = ''
if score < 60:
style = 'style="color: red"'
return '<tr><td>%s</td><td %s>%s</td></tr>' % (name, style, score)
tds = [geneTr(name, score) for name, score in d.items()]
print ('\n'.join(tds))
def geneTr(name, score):
style = ''
if score < 60:
style = 'style="color: red"'
return '<tr><td>%s</td><td %s>%s</td></tr>' % (name, style, score)
tds = [geneTr(name, score) for name, score in d.items()]
print ('\n'.join(tds))
2016-09-15
L1 =[]
L2 =[x + y + z for x in '123456789' for y in '0123456789' for z in '0123456789' if x == z]
for i in L2:
i = int(i)
L1.append(i)
print L1
转成了int还是不可以T.T
L2 =[x + y + z for x in '123456789' for y in '0123456789' for z in '0123456789' if x == z]
for i in L2:
i = int(i)
L1.append(i)
print L1
转成了int还是不可以T.T
2016-09-15
首先一元二次方程的a不能为0，其次得考虑b*b-4*a*c与0的关系，所以我觉得这么写比较好：
def quadratic_equation(a, b, c):
x = b*b-4*a*c
if (a == 0) or (x < 0) :
return
elif x==0:
return (math.sqrt(x) - b ) / (2 * a)
else :
return (math.sqrt(x) - b ) / (2 * a),(-math.sqrt(x) - b ) / (2 * a)
def quadratic_equation(a, b, c):
x = b*b-4*a*c
if (a == 0) or (x < 0) :
return
elif x==0:
return (math.sqrt(x) - b ) / (2 * a)
else :
return (math.sqrt(x) - b ) / (2 * a),(-math.sqrt(x) - b ) / (2 * a)
2016-09-14