make_merge_function#

static rlemasklib.RLEMask.make_merge_function(func, arity=None)[source]#

Create a merge function from a custom n-ary boolean function.

This first calls func with all combinations of n boolean arguments and stores the resulting truth table. It then returns a function that takes n masks and merges them using the truth table.

Parameters:

func (Callable[Ellipsis, bool]) – a callable that takes n bools and returns a bool
arity (Optional[int]) – the number of arguments to the function (default: None, which is determined automatically)

Returns:

A callable that takes masks and returns the merged mask.

Examples

>>> mergefun = RLEMask.make_merge_function(lambda a, b, c: (a | b) & ~c)
>>> rle1 = RLEMask(np.eye(3))
>>> rle2 = RLEMask(np.eye(3)[::-1])
>>> rle3 = RLEMask(np.eye(3, k=-2))
>>> rle = mergefun(rle1, rle2, rle3)
>>> np.array(rle)
array([[1, 0, 1],
       [0, 1, 0],
       [0, 0, 1]], dtype=uint8)