On 10/7/23 16:13, Jens Glaser via NumPy-Discussion wrote:

Hi Matti,

The documentation for numpy.dot currently states

""" out ndarray, optional Output argument. This must have the exact kind that would be returned if it was not used. In particular, it must have the right type, must be C-contiguous, and its dtype must be the dtype that would be returned for dot(a,b). This is a performance feature. Therefore, if these conditions are not met, an exception is raised, instead of attempting to be flexible. """

I think this means that if dot(a,b) returned FP32 for FP16 inputs, it would be consistent with this API to supply a full precision output array. All that would be needed in an actual implementation is a mixed_precision flag (or output_dtype option) for this op to override the usual type promotion rules. Do you agree?

Jens _______________________________________________

`np.dot` is strange. Could you use `np.matmul` instead, which is a real ufunc and (I think) already does this? Matti.