Erlang直方图求和2个映射

Question

如何在erlang中创建两个dicts的直方图和？例如,如果您有2个dicts:

{a: 1, c: 4, d:7} and {a:5, b:8, d:1}

总和将是:

{a:6, b:8, c:4, d:8}

谢谢

Answer 1

假设你的dicts被绑定A并且B变量被重新绑定,那么:

Result = dict:merge(fun (_Key, V1, V2) -> V1 + V2 end, A, B)