如何求和两个列表N元素

时间:2013-04-06 21:47:15

标签: python python-2.7

我需要添加两个数字列表。当一个列表大于另一个列表时,我得到错误“IndexError:list index out of range”。错误发生在行resultado = v1[i] + v2[i]中,但我不知道如何解决它。

我的代码是:

def suma(A, B):

    if len(A) > len(B):
        v1 = A
        v2 = B
    else:
        v1 = B
        v2 = A
    v3 = []
    i = 0
    for i in range(len(v1)):
        resultado = v1[i] + v2[i]
        v3.append(resultado)
    for j in range(len(v1), len(v2)):
        v3.append(v2[j])
    return v3

vectorA = []
vectorB = []
x = 1
while x !=0:
    print "Ingrese los datos para el primer vector (0 para finalizar)"
    x = input("-->>")
    if x !=0:
        vectorA.append (x)

print "=" * 30
x = 1
while x !=0:
    print "Ingrese los datos para el segundo vector (0 para finalizar)"
    x = input("-->>")
    if x !=0:
        vectorB.append (x)

print "=" * 30
print vectorA
print vectorB
print "=" * 30
print "A) SUMA DE VECTORES"
print "=" * 30

suma(vectorA, vectorB)
print suma

3 个答案:

答案 0 :(得分:7)

>>> import itertools
>>> A = [1, 2, 3]
>>> B = [10, 11]
>>> [a + b for a, b in itertools.izip_longest(A, B, fillvalue=0)]
[11, 13, 3]

所以,

def suma(A, B):
    return [a + b for a, b in itertools.izip_longest(A, B, fillvalue=0)]

答案 1 :(得分:2)

您需要itertools.izip_longest

def suma(A, B):
    return map(sum, itertools.izip_longest(A,B, fillvalue=0))

答案 2 :(得分:2)

在这个阶段学习Python可以帮助你更多的是:

导致实际错误是因为您使用较长列表的长度来迭代这两个列表。通过更改

可以轻松解决
for i in range(len(v1)):

进入

for i in range(len(v2)):

因为v2是上面比较后的较短列表。你也应该替换

for j in range(len(v1), len(v2)):        
    v3.append(v2[j])

通过

for j in range(len(v2), len(v1)):        
    v3.append(v1[j])

因为毕竟len(v2)小于len(v1)。最后替换

suma(vectorA, vectorB)
print suma

通过

print suma(vectorA, vectorB)

打印结果。你可以在下面找到工作脚本。

def suma(A, B):

    if len(A) > len(B):
        v1 = A
        v2 = B
    else:
        v1 = B
        v2 = A
    v3 = []
    i = 0
    for i in range(len(v2)):
        resultado = v1[i] + v2[i]
        v3.append(resultado)
    for j in range(len(v2), len(v1)):
        v3.append(v1[j])
    return v3

vectorA = []
vectorB = []
x = 1
while x !=0:
    print "Ingrese los datos para el primer vector (0 para finalizar)"
    x = input("-->>")
    if x !=0:
        vectorA.append (x)

print "=" * 30
x = 1
while x !=0:
    print "Ingrese los datos para el segundo vector (0 para finalizar)"
    x = input("-->>")
    if x !=0:
        vectorB.append (x)

print "=" * 30
print vectorA
print vectorB
print "=" * 30
print "A) SUMA DE VECTORES"
print "=" * 30

print suma(vectorA, vectorB)