d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59, 'Paul': 74 }
sum = 0.0
for k, v in d.items():
sum = sum + v
print k,':',v
print 'average', ':', sum/len(d)
sum = 0.0
for k, v in d.items():
sum = sum + v
print k,':',v
print 'average', ':', sum/len(d)
2016-11-13
d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59, 'Paul': 74 }
sum = 0.0
for i in d.values() :
sum+=i
print sum/len(d )
sum = 0.0
for i in d.values() :
sum+=i
print sum/len(d )
2016-11-13
import math
def quadratic_equation(a, b, c):
m = (-b + math.sqrt(b*b - 4*a*c))/(2*a)
n = (-b - math.sqrt(b*b - 4*a*c))/(2*a)
return m, n
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
def quadratic_equation(a, b, c):
m = (-b + math.sqrt(b*b - 4*a*c))/(2*a)
n = (-b - math.sqrt(b*b - 4*a*c))/(2*a)
return m, n
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2016-11-12
>>> sum=0
>>> x=1
>>> n=1
>>> while True:
sum+=x
x=x*2
n+=1
if n>20:
break
>>> print(sum)
1048575
>>>
>>> x=1
>>> n=1
>>> while True:
sum+=x
x=x*2
n+=1
if n>20:
break
>>> print(sum)
1048575
>>>
2016-11-12
L = [95.5,85,59]
print L[0]
print L[1]
print L[2]
print L[2]
看到很多小伙伴都说 -1,
我喜欢这么写
print L[0]
print L[1]
print L[2]
print L[2]
看到很多小伙伴都说 -1,
我喜欢这么写
2016-11-12
和数学运算不同的地方是,Python的整数运算结果仍然是整数,浮点数运算结果仍然是浮点数:
1 + 2 # ==> 整数 3
1.0 + 2.0 # ==> 浮点数 3.0
但是整数和浮点数混合运算的结果就变成浮点数了:
1 + 2.0 # ==> 浮点数 3.0
1 + 2 # ==> 整数 3
1.0 + 2.0 # ==> 浮点数 3.0
但是整数和浮点数混合运算的结果就变成浮点数了:
1 + 2.0 # ==> 浮点数 3.0
2016-11-12
s = set([('Adam', 95), ('Lisa', 85), ('Bart', 59)])
for x in s:
print x[0],':',x[1]
for x in s:
print x[0],':',x[1]
2016-11-12
d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for x in d :
print x,':',d.get(x)
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for x in d :
print x,':',d.get(x)
2016-11-12