Can numpy einsum() perform outer addition?

问题

In numpy, we can perform "outer addition" between two vectors a and b like this:

a=np.c_[1,2,3]
b=np.c_[4,5,6]
result=a+b.T # alternatively this can be a.T+b

Is it possible to use einsum to make the same calculation? Any other fast alternatives? How about if a equals b?

回答1:

Another fast alternative to this operation is to use:

np.add.outer(a,b)

来源：https://stackoverflow.com/questions/17602796/can-numpy-einsum-perform-outer-addition