misleading error message when using ```hstack```

a = np.random.rand(10, 2)
b = np.random.rand(10, 2)
b = csc_matrix(b)
np.hstack((a, b))

ValueError: all the input arrays must have same number of dimensions

I think it should raise like ‘cannot stack sparse matrix’?

Thanks,

[xuewei4d]

@saullocastro My point is that the error message is not correct

[seberg]

Right, making dtype=object forced if you want an object array… Or maybe an allow_object argument, I am not sure if we even hashed out the details quite. But yes, I think any thought out proposal will be merged quickly 😉.