import math
def quadratic_equation(a, b, c):
delta = math.sqrt(b**2 - 4*a*c) #注意sqrt前面要有math.
return (-b+delta)/2*a, (-b-delta)/2*a
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
def quadratic_equation(a, b, c):
delta = math.sqrt(b**2 - 4*a*c) #注意sqrt前面要有math.
return (-b+delta)/2*a, (-b-delta)/2*a
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2016-11-29
"这种变量本身类型不固定的语言称之为动态语言,与之对应的是静态语言。"。这句话会误人子弟的。python中变量是没有类型的。只有对象才有类型。
2016-11-29
import math
def quadratic_equation(a, b, c):
y = 4*a*c
x = 2*a
delta = math.pow(b,2)-y
if x < 0:
return None
else:
Delta = math.sqrt(delta)
return (-b + Delta)/x,(-b - Delta)/x
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
def quadratic_equation(a, b, c):
y = 4*a*c
x = 2*a
delta = math.pow(b,2)-y
if x < 0:
return None
else:
Delta = math.sqrt(delta)
return (-b + Delta)/x,(-b - Delta)/x
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2016-11-29
L=[str(a)+str(b)+str(c) for a in range(1,10) for b in range(0,10) for c in range(1,10) if str(a) == str(c)]
L=[a+b+c for a in range(100,901,100) for b in range(0,91,10) for c in range(1,10) if a/c==100]
L=[a*100+b*10+c for a in range(1,10) for b in range(0,10) for c in range(1,10) if a == c]
print L
L=[a+b+c for a in range(100,901,100) for b in range(0,91,10) for c in range(1,10) if a/c==100]
L=[a*100+b*10+c for a in range(1,10) for b in range(0,10) for c in range(1,10) if a == c]
print L
2016-11-29
import math
def quadratic_equation(a, b, c):
x1 = (-b+math.sqrt(b**2-4*a*c))/(2*a)
x2 = (-b-math.sqrt(b**2-4*a*c))/(2*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**2-4*a*c))/(2*a)
x2 = (-b-math.sqrt(b**2-4*a*c))/(2*a)
return x1,x2
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2016-11-29
#coding=utf-8
sum = 0
x = 1
n = 1
while True:
sum+=x
x=2**n
n+=1
if n>20:
break
print sum
#利用 while True 无限循环配合 break 语句,计算 1 + 2 + 4 + 8 + 16 + ... 的前20项的和。
sum = 0
x = 1
n = 1
while True:
sum+=x
x=2**n
n+=1
if n>20:
break
print sum
#利用 while True 无限循环配合 break 语句,计算 1 + 2 + 4 + 8 + 16 + ... 的前20项的和。
2016-11-28
s = set(['Adam','Lisa','Bart','Paul'])
2016-11-28
d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for name in d:
print name,':',d[name]
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for name in d:
print name,':',d[name]
2016-11-28
sum = 0
x = 1
while x<100:
if x%2==1:
sum+=x
x=x+1
print sum
x = 1
while x<100:
if x%2==1:
sum+=x
x=x+1
print sum
2016-11-28