Primitives work & Reverse differentiation

[never-to-never]

I registered a primitive function func_primitive, for example: out=func_primitive(arg1, arg2, arg3). When I used grad(func_primitive), it reported "NotImplementedError: Transpose rule (for reverse-mode differentiation) for 'multiply_add' not implemented". Now I should implement the ad.primitive_transposes rule;
Now I can't understand the instructions provided by "https://jax.readthedocs.io/en/latest/notebooks/How_JAX_primitives_work.html#reverse-differentiation" and would like to ask:
When implementing the ad.primitive_transposes method, what should be returned?

[jakevdp]

Hi - there are a bunch of examples of transpose function ouputs near the section you linked to: https://jax.readthedocs.io/en/latest/notebooks/How_JAX_primitives_work.html#transposition

I'm not sure what additional information I can give here that would add clarity to those examples. Do you have any specific point of confusion after looking through that section?