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First couple scenes of bayes
This commit is contained in:
Grant Sanderson
788
3b1b_projects/active/bayes.py
Normal file
788
3b1b_projects/active/bayes.py
Normal file
@ -0,0 +1,788 @@
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from manimlib.imports import *
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OUTPUT_DIRECTORY = "bayes"
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HYPOTHESIS_COLOR = YELLOW
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NOT_HYPOTHESIS_COLOR = GREY
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EVIDENCE_COLOR1 = BLUE_C
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EVIDENCE_COLOR2 = BLUE_D
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NOT_EVIDENCE_COLOR1 = RED
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NOT_EVIDENCE_COLOR2 = RED_E
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#
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def get_bayes_formula(expand_denominator=False):
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t2c = {
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"{H}": HYPOTHESIS_COLOR,
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"{\\neg H}": NOT_HYPOTHESIS_COLOR,
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"{E}": EVIDENCE_COLOR1,
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}
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substrings_to_isolate = ["P", "\\over", "=", "\\cdot", "+"]
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tex = "P({H} | {E}) = {P({H}) \\cdot P({E} | {H}) \\over "
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if expand_denominator:
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tex += "P({H}) \\cdot P({E} | {H}) + P({\\neg H}) \\cdot P({E} | {\\neg H})}"
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else:
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tex += "P({E})}"
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formula = TexMobject(
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tex,
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tex_to_color_map=t2c,
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substrings_to_isolate=substrings_to_isolate,
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)
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formula.posterior = formula[:6]
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formula.prior = formula[8:12]
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formula.likelihood = formula[13:19]
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if expand_denominator:
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pass
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formula.denom_prior = formula[20:24]
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formula.denom_likelihood = formula[25:31]
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formula.denom_anti_prior = formula[32:36]
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formula.denom_anti_likelihood = formula[37:42]
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else:
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formula.p_evidence = formula[20:]
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return formula
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class BayesDiagram(VGroup):
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CONFIG = {
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"height": 2,
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"square_style": {
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"fill_color": DARK_GREY,
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"fill_opacity": 1,
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"stroke_color": WHITE,
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"stroke_width": 2,
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},
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"rect_style": {
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"stroke_color": WHITE,
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"stroke_width": 1,
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"fill_opacity": 1,
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},
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"hypothesis_color": HYPOTHESIS_COLOR,
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"not_hypothesis_color": NOT_HYPOTHESIS_COLOR,
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"evidence_color1": EVIDENCE_COLOR1,
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"evidence_color2": EVIDENCE_COLOR2,
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"not_evidence_color1": NOT_EVIDENCE_COLOR1,
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"not_evidence_color2": NOT_EVIDENCE_COLOR2,
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}
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def __init__(self, prior, likelihood, antilikelihood, **kwargs):
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super().__init__(**kwargs)
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square = Square(side_length=self.height)
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square.set_style(**self.square_style)
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# Create all rectangles
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h_rect, nh_rect, he_rect, nhe_rect, hne_rect, nhne_rect = [
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square.copy().set_style(**self.rect_style)
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for x in range(6)
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]
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# Add as attributes
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self.square = square
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self.h_rect = h_rect # Hypothesis
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self.nh_rect = nh_rect # Not hypothesis
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self.he_rect = he_rect # Hypothesis and evidence
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self.hne_rect = hne_rect # Hypothesis and not evidence
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self.nhe_rect = nhe_rect # Not hypothesis and evidence
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self.nhne_rect = nhne_rect # Not hypothesis and not evidence
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# Stretch the rectangles
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for rect in h_rect, he_rect, hne_rect:
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rect.stretch(prior, 0, about_edge=LEFT)
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for rect in nh_rect, nhe_rect, nhne_rect:
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rect.stretch(1 - prior, 0, about_edge=RIGHT)
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he_rect.stretch(likelihood, 1, about_edge=DOWN)
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hne_rect.stretch(1 - likelihood, 1, about_edge=UP)
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nhe_rect.stretch(antilikelihood, 1, about_edge=DOWN)
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nhne_rect.stretch(1 - antilikelihood, 1, about_edge=UP)
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# Color the rectangles
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h_rect.set_fill(self.hypothesis_color)
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nh_rect.set_fill(self.not_hypothesis_color)
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he_rect.set_fill(self.evidence_color1)
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hne_rect.set_fill(self.not_evidence_color1)
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nhe_rect.set_fill(self.evidence_color2)
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nhne_rect.set_fill(self.not_evidence_color2)
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# Add them
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self.hypothesis_split = VGroup(h_rect, nh_rect)
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self.evidence_split = VGroup(he_rect, hne_rect, nhe_rect, nhne_rect)
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# Don't add hypothesis split by default
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self.add(self.square, self.evidence_split)
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def generate_braces(self):
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pass # TODO
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class ProbabilityBar(VGroup):
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CONFIG = {
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"color1": BLUE_D,
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"color2": GREY_BROWN,
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"height": 0.5,
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"width": 6,
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"rect_style": {
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"stroke_width": 1,
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"stroke_color": WHITE,
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"fill_opacity": 1,
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},
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"include_braces": True,
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"brace_direction": UP,
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"include_percentages": True,
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}
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def __init__(self, p=0.5, **kwargs):
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super().__init__(**kwargs)
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self.add_backbone()
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self.add_p_tracker(p)
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self.add_bars()
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if self.include_braces:
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self.braces = always_redraw(lambda: self.get_braces())
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self.add(self.braces)
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if self.include_percentages:
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self.percentages = always_redraw(lambda: self.get_percentages())
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self.add(self.percentages)
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def add_backbone(self):
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backbone = Line()
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backbone.set_opacity(0)
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backbone.set_width(self.width)
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self.backbone = backbone
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self.add(backbone)
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def add_p_tracker(self, p):
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self.p_tracker = ValueTracker(p)
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def add_bars(self):
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bars = VGroup(Rectangle(), Rectangle())
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bars.set_height(self.height)
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colors = [self.color1, self.color2]
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for bar, color in zip(bars, colors):
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bar.set_style(**self.rect_style)
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bar.set_fill(color=color)
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bars.add_updater(self.update_bars)
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self.bars = bars
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self.add(bars)
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def update_bars(self, bars):
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vects = [LEFT, RIGHT]
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p = self.p_tracker.get_value()
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values = [p, 1 - p]
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total_width = self.backbone.get_width()
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for bar, vect, value in zip(bars, vects, values):
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bar.set_width(value * total_width, stretch=True)
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bar.move_to(self.backbone, vect)
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return bars
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def get_braces(self):
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return VGroup(*[
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Brace(
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bar,
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self.brace_direction,
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min_num_quads=1,
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buff=SMALL_BUFF,
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)
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for bar in self.bars
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])
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def get_percentages(self):
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p = self.p_tracker.get_value()
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labels = VGroup(*[
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Integer(value, unit="\\%")
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for value in [
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np.floor(p * 100),
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100 - np.floor(p * 100),
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]
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])
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for label, bar in zip(labels, self.bars):
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label.set_height(0.75 * bar.get_height())
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min_width = 0.75 * bar.get_width()
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if label.get_width() > min_width:
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label.set_width(min_width)
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label.move_to(bar)
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label.set_stroke(BLACK, 5, background=True)
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return labels
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def add_icons(self, *icons, buff=SMALL_BUFF):
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if hasattr(self, "braces"):
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refs = self.braces
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else:
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refs = self.bars
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for icon, ref in zip(icons, refs):
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icon.ref = ref
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icon.add_updater(lambda i: i.next_to(
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i.ref,
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self.brace_direction,
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buff=buff
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))
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self.icons = VGroup(*icons)
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self.add(self.icons)
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class Steve(SVGMobject):
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CONFIG = {
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"file_name": "steve",
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"fill_color": GREY,
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"sheen_factor": 0.5,
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"sheen_direction": UL,
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"stroke_width": 0,
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"height": 3,
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"include_name": True,
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}
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def __init__(self, **kwargs):
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super().__init__(**kwargs)
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if self.include_name:
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self.add_name()
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def add_name(self):
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self.name = TextMobject("Steve")
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self.name.match_width(self)
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self.name.next_to(self, DOWN, SMALL_BUFF)
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self.add(self.name)
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class LibrarianIcon(SVGMobject):
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CONFIG = {
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"file_name": "book",
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"stroke_width": 0,
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"fill_color": LIGHT_GREY,
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"sheen_factor": 0.5,
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"sheen_direction": UL,
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"height": 0.75,
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}
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def __init__(self, **kwargs):
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super().__init__(**kwargs)
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class FarmerIcon(SVGMobject):
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CONFIG = {
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# "file_name": "pitch_fork_and_roll",
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"file_name": "farming",
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"stroke_width": 0,
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"fill_color": GREEN_E,
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"sheen_factor": 0.5,
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"sheen_direction": UL,
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"height": 1.5,
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}
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def __init__(self, **kwargs):
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super().__init__(**kwargs)
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# Scenes
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# class Test(Scene):
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# def construct(self):
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# icon = FarmerIcon()
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# icon.scale(2)
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# self.add(icon)
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# # self.add(get_submobject_index_labels(icon))
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# class FullFormulaIndices(Scene):
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# def construct(self):
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# formula = get_bayes_formula(expand_denominator=True)
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# formula.set_width(FRAME_WIDTH - 1)
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# self.add(formula)
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# self.add(get_submobject_index_labels(formula))
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class IntroduceFormula(Scene):
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def construct(self):
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formula = get_bayes_formula()
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formula.set_width(FRAME_WIDTH - 1)
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def get_formula_slice(*indices):
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return VGroup(*[formula[i] for i in indices])
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H_label = formula.get_part_by_tex("{H}")
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E_label = formula.get_part_by_tex("{E}")
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hyp_label = TextMobject("Hypothesis")
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hyp_label.set_color(HYPOTHESIS_COLOR)
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hyp_label.next_to(H_label, UP, LARGE_BUFF)
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evid_label = TextMobject("Evidence")
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evid_label.set_color(EVIDENCE_COLOR1)
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evid_label.next_to(E_label, DOWN, LARGE_BUFF)
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hyp_arrow = Arrow(hyp_label.get_bottom(), H_label.get_top(), buff=SMALL_BUFF)
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evid_arrow = Arrow(evid_label.get_top(), E_label.get_bottom(), buff=SMALL_BUFF)
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self.add(formula[:6])
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# self.add(get_submobject_index_labels(formula))
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# return
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self.play(
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FadeInFrom(hyp_label, DOWN),
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GrowArrow(hyp_arrow),
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FadeInFrom(evid_label, UP),
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GrowArrow(evid_arrow),
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)
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self.wait()
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# Prior
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self.play(
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ShowCreation(formula.get_part_by_tex("=")),
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TransformFromCopy(
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get_formula_slice(0, 1, 2, 5),
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get_formula_slice(8, 9, 10, 11),
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),
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)
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self.wait()
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# Likelihood
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lhs_copy = formula[:6].copy()
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likelihood = formula[13:19]
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run_time = 1
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self.play(
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lhs_copy.next_to, likelihood, UP,
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DrawBorderThenFill(formula.get_part_by_tex("\\cdot")),
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run_time=run_time,
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)
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self.play(
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Swap(lhs_copy[2], lhs_copy[4]),
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run_time=run_time,
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)
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self.play(
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lhs_copy.move_to, likelihood,
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run_time=run_time,
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)
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self.wait()
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# Evidence
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self.play(
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ShowCreation(formula.get_part_by_tex("\\over")),
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TransformFromCopy(
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get_formula_slice(0, 1, 4, 5),
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get_formula_slice(20, 21, 22, 23),
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),
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)
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self.wait()
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class StateGoal(PiCreatureScene):
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CONFIG = {
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"default_pi_creature_kwargs": {
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"color": BLUE_B,
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"height": 2,
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},
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}
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def construct(self):
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you = self.pi_creature
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line = NumberLine(
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x_min=-2,
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x_max=12,
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include_tip=True
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)
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line.to_edge(DOWN, buff=1.5)
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line.to_edge(LEFT, buff=-0.5)
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you.next_to(line.n2p(0), UP)
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you_label = TextMobject("you")
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you_label.next_to(you, RIGHT, MED_LARGE_BUFF)
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you_arrow = Arrow(you_label.get_left(), you.get_right() + 0.5 * LEFT, buff=0.1)
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now_label = TextMobject("Now")
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later_label = TextMobject("Later")
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now_label.next_to(line.n2p(0), DOWN)
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later_label.next_to(line.n2p(10), DOWN)
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self.add(line, now_label)
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self.add(you)
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self.play(
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FadeInFrom(you_label, LEFT),
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GrowArrow(you_arrow),
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you.change, "pondering",
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)
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self.wait()
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you_label.add(you_arrow)
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self.play(
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you.change, "horrified",
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you.look, DOWN,
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you.next_to, line.n2p(10), UP,
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MaintainPositionRelativeTo(you_label, you),
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FadeInFromPoint(later_label, now_label.get_center()),
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)
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self.wait()
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||||
bubble = you.get_bubble(
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||||
height=4,
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||||
width=6,
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)
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bubble.set_fill(opacity=0)
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formula = get_bayes_formula()
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bubble.position_mobject_inside(formula)
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self.play(
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you.change, "confused", bubble,
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ShowCreation(bubble),
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||||
)
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self.play(FadeIn(formula))
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||||
self.play(you.change, "hooray", formula)
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||||
self.wait(2)
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||||
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# Levels of understanding
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# Turn bubble into level points
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level_points = VGroup(*[bubble.copy() for x in range(3)])
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for n, point in enumerate(level_points):
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point.set_width(0.5)
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point.set_height(0.5, stretch=True)
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point.add(*[
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point[-1].copy().scale(1.2**k)
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for k in range(1, n + 1)
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])
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||||
point[:3].scale(1.2**n, about_point=point[3].get_center())
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||||
point.set_stroke(width=2)
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||||
point.set_fill(opacity=0)
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||||
level_points.arrange(DOWN, buff=LARGE_BUFF)
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||||
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||||
title = TextMobject("Levels of understanding")
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||||
title.scale(1.5)
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title.to_corner(UL)
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||||
underline = Line()
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||||
underline.match_width(title)
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||||
underline.move_to(title, DOWN)
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||||
title.add(underline)
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||||
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||||
level_points.next_to(title, DOWN, buff=1.5)
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||||
level_points.to_edge(LEFT)
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||||
level_points.set_submobject_colors_by_gradient(GREEN, YELLOW, RED)
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||||
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||||
self.remove(bubble)
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||||
self.play(
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||||
formula.to_corner, UR,
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||||
Uncreate(line),
|
||||
FadeOutAndShift(now_label, DOWN),
|
||||
FadeOutAndShift(later_label, DOWN),
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||||
FadeOut(you_label),
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||||
FadeOut(you_arrow),
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||||
FadeOut(you),
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||||
*[
|
||||
ReplacementTransform(bubble.copy(), point)
|
||||
for point in level_points
|
||||
],
|
||||
)
|
||||
self.play(Write(title, run_time=1))
|
||||
self.wait()
|
||||
|
||||
# Write level 1
|
||||
level_labels = VGroup(
|
||||
TextMobject("What is it saying?"),
|
||||
TextMobject("Why is it true?"),
|
||||
TextMobject("When is it useful?"),
|
||||
)
|
||||
for lp, ll in zip(level_points, level_labels):
|
||||
ll.scale(1.25)
|
||||
ll.match_color(lp)
|
||||
ll.next_to(lp, RIGHT)
|
||||
|
||||
formula_parts = VGroup(
|
||||
formula.prior,
|
||||
formula.likelihood,
|
||||
formula.p_evidence,
|
||||
formula.posterior,
|
||||
).copy()
|
||||
formula_parts.generate_target()
|
||||
formula_parts.target.scale(1.5)
|
||||
formula_parts.target.arrange(DOWN, buff=LARGE_BUFF, aligned_edge=LEFT)
|
||||
formula_parts.target.next_to(formula, DOWN, buff=LARGE_BUFF)
|
||||
formula_parts.target.shift(3 * LEFT)
|
||||
|
||||
equal_signs = VGroup(*[
|
||||
TextMobject("=").next_to(fp, RIGHT)
|
||||
for fp in formula_parts.target
|
||||
])
|
||||
|
||||
kw = {
|
||||
"tex_to_color_map": {
|
||||
"hypothesis": HYPOTHESIS_COLOR,
|
||||
"evidence": EVIDENCE_COLOR1,
|
||||
},
|
||||
"alignment": "",
|
||||
}
|
||||
meanings = VGroup(
|
||||
TextMobject("Probability a hypothesis is true\\\\(before any evidence)", **kw),
|
||||
TextMobject("Probability of seeing the evidence \\quad \\\\if the hypothesis is true", **kw),
|
||||
TextMobject("Probability of seeing the evidence", **kw),
|
||||
TextMobject("Probability a hypothesis is true\\\\given some evidence", **kw),
|
||||
)
|
||||
for meaning, equals in zip(meanings, equal_signs):
|
||||
meaning.scale(0.5)
|
||||
meaning.next_to(equals, RIGHT)
|
||||
|
||||
self.play(
|
||||
FadeIn(level_labels[0], lag_ratio=0.1),
|
||||
MoveToTarget(formula_parts),
|
||||
LaggedStartMap(FadeInFrom, equal_signs, lambda m: (m, RIGHT)),
|
||||
LaggedStartMap(FadeIn, meanings),
|
||||
)
|
||||
self.wait()
|
||||
|
||||
# Write level 2
|
||||
diagram = BayesDiagram(0.35, 0.5, 0.2, height=2.5)
|
||||
diagram.next_to(formula, DOWN, aligned_edge=LEFT)
|
||||
|
||||
braces = VGroup(*[
|
||||
Brace(diagram.he_rect, vect, buff=SMALL_BUFF)
|
||||
for vect in [DOWN, LEFT]
|
||||
])
|
||||
|
||||
formula_parts.generate_target()
|
||||
formula_parts.target[:2].scale(0.5)
|
||||
formula_parts.target[0].next_to(braces[0], DOWN, SMALL_BUFF)
|
||||
formula_parts.target[1].next_to(braces[1], LEFT, SMALL_BUFF)
|
||||
|
||||
pe_picture = VGroup(
|
||||
diagram.he_rect.copy(),
|
||||
TexMobject("+"),
|
||||
diagram.nhe_rect.copy()
|
||||
)
|
||||
pe_picture.arrange(RIGHT, buff=SMALL_BUFF)
|
||||
pe_picture.next_to(equal_signs[2], RIGHT)
|
||||
|
||||
phe_picture = VGroup(
|
||||
diagram.he_rect.copy(),
|
||||
Line().match_width(pe_picture),
|
||||
pe_picture.copy(),
|
||||
)
|
||||
phe_picture.arrange(DOWN, buff=MED_SMALL_BUFF)
|
||||
phe_picture.next_to(equal_signs[3], RIGHT)
|
||||
|
||||
pe_picture.scale(0.5, about_edge=LEFT)
|
||||
phe_picture.scale(0.3, about_edge=LEFT)
|
||||
|
||||
self.play(
|
||||
FadeOut(meanings),
|
||||
FadeOut(equal_signs[:2]),
|
||||
MoveToTarget(formula_parts),
|
||||
FadeIn(diagram),
|
||||
LaggedStartMap(GrowFromCenter, braces),
|
||||
FadeIn(level_labels[1], lag_ratio=0.1),
|
||||
level_labels[0].set_opacity, 0.5,
|
||||
)
|
||||
self.play(
|
||||
TransformFromCopy(diagram.he_rect, pe_picture[0]),
|
||||
TransformFromCopy(diagram.nhe_rect, pe_picture[2]),
|
||||
FadeIn(pe_picture[1]),
|
||||
)
|
||||
self.play(
|
||||
TransformFromCopy(pe_picture, phe_picture[2]),
|
||||
TransformFromCopy(pe_picture[0], phe_picture[0]),
|
||||
ShowCreation(phe_picture[1])
|
||||
)
|
||||
self.wait()
|
||||
|
||||
# Write level 3
|
||||
steve = Steve(height=3)
|
||||
steve.to_edge(RIGHT, buff=2)
|
||||
|
||||
arrow = Arrow(level_points.get_bottom(), level_points.get_top(), buff=0)
|
||||
arrow.shift(0.25 * LEFT)
|
||||
|
||||
self.play(
|
||||
LaggedStartMap(
|
||||
FadeOutAndShift,
|
||||
VGroup(
|
||||
VGroup(diagram, braces, formula_parts[:2]),
|
||||
VGroup(formula_parts[2], equal_signs[2], pe_picture),
|
||||
VGroup(formula_parts[3], equal_signs[3], phe_picture),
|
||||
),
|
||||
lambda m: (m, 3 * RIGHT),
|
||||
),
|
||||
FadeIn(level_labels[2], lag_ratio=0.1),
|
||||
level_labels[1].set_opacity, 0.5,
|
||||
)
|
||||
self.wait()
|
||||
self.play(
|
||||
GrowArrow(arrow),
|
||||
level_points.shift, 0.5 * RIGHT,
|
||||
level_labels.shift, 0.5 * RIGHT,
|
||||
level_labels.set_opacity, 1,
|
||||
)
|
||||
self.wait()
|
||||
self.play(Write(steve, run_time=3))
|
||||
self.wait()
|
||||
|
||||
# Transition to next scene
|
||||
self.play(
|
||||
steve.to_corner, UR,
|
||||
Uncreate(arrow),
|
||||
LaggedStartMap(
|
||||
FadeOutAndShift,
|
||||
VGroup(
|
||||
title,
|
||||
formula,
|
||||
*level_points,
|
||||
*level_labels,
|
||||
),
|
||||
lambda m: (m, DOWN),
|
||||
),
|
||||
)
|
||||
self.wait()
|
||||
|
||||
|
||||
class DescriptionOfSteve(Scene):
|
||||
def construct(self):
|
||||
self.write_description()
|
||||
self.compare_probabilities()
|
||||
|
||||
def write_description(self):
|
||||
steve = Steve(height=3)
|
||||
steve.to_corner(UR)
|
||||
|
||||
description = TextMobject(
|
||||
"""
|
||||
Steve is very shy and withdrawn,\\\\
|
||||
invariably helpful but with very\\\\
|
||||
little interest in people or in the\\\\
|
||||
world of reality. A meek and tidy\\\\
|
||||
soul, he has a need for order and\\\\
|
||||
structure, and a passion for detail.\\\\
|
||||
""",
|
||||
tex_to_color_map={
|
||||
"shy and withdrawn": BLUE,
|
||||
"meek and tidy": WHITE,
|
||||
"soul": WHITE,
|
||||
},
|
||||
alignment="",
|
||||
)
|
||||
description.to_edge(LEFT)
|
||||
description.match_y(steve)
|
||||
|
||||
self.add(steve)
|
||||
self.play(
|
||||
FadeIn(description),
|
||||
run_time=3,
|
||||
lag_ratio=0.01,
|
||||
rate_func=linear,
|
||||
)
|
||||
self.wait(3)
|
||||
|
||||
mt_parts = VGroup(
|
||||
description.get_part_by_tex("meek"),
|
||||
description.get_part_by_tex("soul"),
|
||||
)
|
||||
lines = VGroup(*[
|
||||
Line(mob.get_corner(DL), mob.get_corner(DR), color=YELLOW)
|
||||
for mob in mt_parts
|
||||
])
|
||||
self.play(
|
||||
ShowCreation(lines),
|
||||
mt_parts.set_color, YELLOW,
|
||||
)
|
||||
self.play(FadeOut(lines))
|
||||
self.wait()
|
||||
|
||||
def compare_probabilities(self):
|
||||
bar = ProbabilityBar(0.5, width=10)
|
||||
icons = VGroup(
|
||||
LibrarianIcon(),
|
||||
FarmerIcon(),
|
||||
)
|
||||
for icon, text, half in zip(icons, ["Librarian", "Farmer"], bar.bars):
|
||||
icon.set_height(0.7)
|
||||
label = TextMobject(text)
|
||||
label.next_to(icon, DOWN, buff=SMALL_BUFF)
|
||||
label.set_color(
|
||||
interpolate_color(half.get_color(), WHITE, 0.5)
|
||||
)
|
||||
icon.add(label)
|
||||
|
||||
bar.add_icons(*icons)
|
||||
bar.move_to(1.75 * DOWN)
|
||||
|
||||
bar.icons.set_opacity(0)
|
||||
|
||||
q_marks = TexMobject(*"???")
|
||||
q_marks.scale(1.5)
|
||||
q_marks.space_out_submobjects(1.5)
|
||||
q_marks.next_to(bar, DOWN)
|
||||
|
||||
self.play(FadeIn(bar))
|
||||
self.wait()
|
||||
self.play(
|
||||
bar.p_tracker.set_value, 0.9,
|
||||
bar.icons[0].set_opacity, 1,
|
||||
)
|
||||
self.wait()
|
||||
self.play(
|
||||
bar.p_tracker.set_value, 0.1,
|
||||
bar.icons[1].set_opacity, 1,
|
||||
)
|
||||
self.play(
|
||||
LaggedStartMap(
|
||||
FadeInFrom, q_marks,
|
||||
lambda m: (m, UP),
|
||||
run_time=2,
|
||||
),
|
||||
ApplyMethod(
|
||||
bar.p_tracker.set_value, 0.7,
|
||||
run_time=8,
|
||||
)
|
||||
)
|
||||
for value in 0.3, 0.7:
|
||||
self.play(
|
||||
bar.p_tracker.set_value, 0.3,
|
||||
run_time=7,
|
||||
)
|
||||
|
||||
|
||||
class IntroduceKahnemanAndTversky(Scene):
|
||||
def construct(self):
|
||||
images = Group(
|
||||
ImageMobject("kahneman"),
|
||||
ImageMobject("tversky"),
|
||||
)
|
||||
danny, amos = images
|
||||
images.set_height(3.5)
|
||||
images.arrange(DOWN, buff=0.5)
|
||||
images.to_edge(LEFT, buff=MED_LARGE_BUFF)
|
||||
|
||||
names = VGroup(
|
||||
TextMobject("Daniel\\\\Kahneman", alignment=""),
|
||||
TextMobject("Amos\\\\Tversky", alignment=""),
|
||||
)
|
||||
for name, image in zip(names, images):
|
||||
name.scale(1.25)
|
||||
name.next_to(image, RIGHT)
|
||||
image.name = name
|
||||
|
||||
prize = ImageMobject("nobel_prize", height=1)
|
||||
prize.move_to(danny, UR)
|
||||
prize.shift(MED_SMALL_BUFF * UR)
|
||||
|
||||
books = Group(
|
||||
ImageMobject("thinking_fast_and_slow"),
|
||||
ImageMobject("undoing_project"),
|
||||
)
|
||||
books.set_height(5)
|
||||
books.arrange(RIGHT, buff=0.5)
|
||||
books.to_edge(RIGHT, buff=MED_LARGE_BUFF)
|
||||
|
||||
self.play(
|
||||
FadeInFrom(danny, DOWN),
|
||||
FadeInFrom(danny.name, LEFT),
|
||||
)
|
||||
self.play(
|
||||
FadeInFrom(amos, UP),
|
||||
FadeInFrom(amos.name, LEFT),
|
||||
)
|
||||
self.wait()
|
||||
self.play(FadeInFromLarge(prize))
|
||||
self.wait()
|
||||
for book in books:
|
||||
self.play(FadeInFrom(book, LEFT))
|
||||
self.wait()
|
||||
Reference in New Issue
Block a user