如何从python中的两个词典构造一个字典？

Question

假设我有一本字典:

x = {"x1":1,"x2":2,"x3":3}

我有另一本字典:

y = {"y1":1,"y2":2,"y3":3}

有没有任何巧妙的方法来构建前两个字典中的第三个字典:

z = {"y1":1,"x2":2,"x1":1,"y2":2}  

Answer 1

如果你想要整个2个dicts:

x = {"x1":1,"x2":2,"x3":3}
y = {"y1":1,"y2":2,"y3":3}


z = dict(x.items() + y.items())
print z

输出:

{'y2': 2, 'y1': 1, 'x2': 2, 'x3': 3, 'y3': 3, 'x1': 1}

如果你想要部分字典:

x = {"x1":1,"x2":2,"x3":3}
y = {"y1":1,"y2":2,"y3":3}

keysList = ["x2", "x1", "y1", "y2"]
z = {}

for key, value in dict(x.items() + y.items()).iteritems():
    if key in keysList:
        z.update({key: value})

print z

产量

{'y1': 1, 'x2': 2, 'x1': 1, 'y2': 2}

Answer 2

然后，您可以使用copyfor 从以下项添加键和值：xupdatey

z = x.copy()
z.update(y)