Artificial rows this prior contributes, for restrictions on sums.
Defaults to none, which is the statement that this prior’s content is
entirely in its moments.
- Parameters:
context (_PriorContext) – What the prior needs to know about the sample.
- Return type:
tuple[NDArray[double], NDArray[double]]
- Returns:
A (rows, k) target block and a (rows, width) design block.
