python - Choose elements from two numpy arrays at random -

i trying merge 2 numpy arrays choosing elements each @ random. have 2 arrays of equal length x , y follows:

x = np.arange(10) y = np.arange(10, 20)

and mask r:

r = np.random.choice([true, false], 10)

then there way select elements x r true , y r false?

i don't have use mask approach, need fast x , y longer 10 in reality ideally no looping involved.

how this?

z = y.copy() z[r] = x[r]

Ben