Originally posted by ttzytt February 22, 2023
Found some places to improve when using the package to implement the animation of a simple binary search algorithm:
class MyScene(Scene):
def construct(self):
arr = MArray(self, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
arr.shift(LEFT * 4 + UP * 2)
tar_val = MVariable(self, 3, label="target value")
tar_val.shift(DOWN * 2)
l = MArrayPointer(self, arr, 0, label="left")
r = MArrayPointer(self, arr, 9, label="right")
self.play(Create(arr))
self.play(Create(tar_val))
self.play(Create(l))
self.play(Create(r))
mid = MArrayPointer(self, arr, (l.fetch_index() + r.fetch_index()) // 2, label="mid")
self.play(Create(mid))
# find first larger or equal to target value
while (l.fetch_index() <= r.fetch_index()):
anims = []
if (mid.fetch_index() < tar_val.fetch_value()):
anims.append(l.shift_to_elem(mid.fetch_index() + 1, play_anim=False))
else:
anims.append(r.shift_to_elem(mid.fetch_index() - 1, play_anim=False))
anims.append(mid.shift_to_elem((l.fetch_index() + r.fetch_index()) // 2, play_anim=False))
self.play(AnimationGroup(*anims))
self.wait(1)For every comparison between MArrayPointer, you have to call fetch_index() to get the position where the array is pointing. I think it will be better to overload comparators in MArrayPointer so that the implementation will be easier.
The same works for other operators like add and subtract: the addition or subtraction between MArrayPointer an integer or another MArrayPointer should give the addition and subtraction between the integer and the index that the pointer is pointing to in a MArray. That way, the operation of pointers will be much easier, and code like the following will be simplified:
r.shift_to_elem(mid.fetch_index() - 1, play_anim=False
mid.shift_to_elem((l.fetch_index() + r.fetch_index()) // 2
Another possible improvement from overloading operators is to overload __getitem__ and __setitem__ for MArray. Using these two methods, we could directly access the MArrayElement inside the MArray through the bracket operator, thus making animations on MArrayElement in an easier way.
I'm not sure about your ideas for these modifications, but if you think they are helpful, I can make a PR on that.
Discussed in #17
Originally posted by ttzytt February 22, 2023
Found some places to improve when using the package to implement the animation of a simple binary search algorithm:
For every comparison between
MArrayPointer, you have to callfetch_index()to get the position where the array is pointing. I think it will be better to overload comparators in MArrayPointer so that the implementation will be easier.The same works for other operators like add and subtract: the addition or subtraction between
MArrayPointeran integer or anotherMArrayPointershould give the addition and subtraction between the integer and the index that the pointer is pointing to in aMArray. That way, the operation of pointers will be much easier, and code like the following will be simplified:r.shift_to_elem(mid.fetch_index() - 1, play_anim=Falsemid.shift_to_elem((l.fetch_index() + r.fetch_index()) // 2Another possible improvement from overloading operators is to overload
__getitem__and__setitem__forMArray. Using these two methods, we could directly access theMArrayElementinside theMArraythrough the bracket operator, thus making animations onMArrayElementin an easier way.I'm not sure about your ideas for these modifications, but if you think they are helpful, I can make a PR on that.
@ttzytt Please provide details for which classes and operators you think should be overloaded.