def add_arrows(self, true_length = False):
if not hasattr(self, "function"):
raise Exception("Must run use_function first")
points = self.get_points(self.arrow_spacing)
points = filter(
lambda p : np.linalg.norm(self.function(p)) > 0.01,
points
)
angles = map(angle_of_vector, map(self.function, points))
prototype = Arrow(
ORIGIN, RIGHT*self.arrow_spacing/2.,
color = self.arrow_color,
tip_length = 0.1,
buff = 0
)
arrows = []
for point in points:
arrow = prototype.copy()
output = self.function(point)
if true_length:
arrow.scale(np.linalg.norm(output))
arrow.rotate(angle_of_vector(output))
arrow.shift(point)
arrows.append(arrow)
self.arrows = Mobject(*arrows)
self.play(ShowCreation(self.arrows))
self.dither()
