def get_graph_label(
self,
graph,
label="f(x)",
x_val=None,
direction=RIGHT,
buff=MED_SMALL_BUFF,
color=None,
):
label = TexMobject(label)
color = color or graph.get_color()
label.set_color(color)
if x_val is None:
# Search from right to left
for x in np.linspace(self.x_max, self.x_min, 100):
point = self.input_to_graph_point(x, graph)
if point[1] < FRAME_Y_RADIUS:
break
x_val = x
label.next_to(
self.input_to_graph_point(x_val, graph),
direction,
buff=buff
)
label.shift_onto_screen()
return label
def add_axes(self):
x_axis = Line(self.tick_width * LEFT / 2, self.width * RIGHT)
y_axis = Line(MED_LARGE_BUFF * DOWN, self.height * UP)
ticks = VGroup()
heights = np.linspace(0, self.height, self.n_ticks + 1)
values = np.linspace(0, self.max_value, self.n_ticks + 1)
for y, value in zip(heights, values):
tick = Line(LEFT, RIGHT)
tick.set_width(self.tick_width)
tick.move_to(y * UP)
ticks.add(tick)
y_axis.add(ticks)
self.add(x_axis, y_axis)
self.x_axis, self.y_axis = x_axis, y_axis
if self.label_y_axis:
labels = VGroup()
for tick, value in zip(ticks, values):
label = TexMobject(str(np.round(value, 2)))
label.set_height(self.y_axis_label_height)
label.next_to(tick, LEFT, SMALL_BUFF)
labels.add(label)
self.y_axis_labels = labels
self.add(labels)
def add_T_label(self, x_val, side=RIGHT, label=None, color=WHITE, animated=False, **kwargs):
triangle = RegularPolygon(n=3, start_angle=np.pi / 2)
triangle.set_height(MED_SMALL_BUFF)
triangle.move_to(self.coords_to_point(x_val, 0), UP)
triangle.set_fill(color, 1)
triangle.set_stroke(width=0)
if label is None:
T_label = TexMobject(self.variable_point_label, fill_color=color)
else:
T_label = TexMobject(label, fill_color=color)
T_label.next_to(triangle, DOWN)
v_line = self.get_vertical_line_to_graph(
x_val, self.v_graph,
color=YELLOW
)
if animated:
self.play(
DrawBorderThenFill(triangle),
ShowCreation(v_line),
Write(T_label, run_time=1),
**kwargs
)
if np.all(side == LEFT):
self.left_T_label_group = VGroup(T_label, triangle)
self.left_v_line = v_line
self.add(self.left_T_label_group, self.left_v_line)
elif np.all(side == RIGHT):
self.right_T_label_group = VGroup(T_label, triangle)
self.right_v_line = v_line
self.add(self.right_T_label_group, self.right_v_line)
def construct(self):
eq1a = TexMobject("4x + 3y")
eq1b = TexMobject("=")
eq1c = TexMobject("0")
eq2a = TexMobject("5x - 2y")
eq2b = TexMobject("=")
eq2c = TexMobject("3")
eq1b.next_to(eq1a, RIGHT)
eq1c.next_to(eq1b, RIGHT)
eq2a.shift(DOWN)
eq2b.shift(DOWN)
eq2c.shift(DOWN)
eq2a.align_to(eq1a, LEFT)
eq2b.align_to(eq1b, LEFT)
eq2c.align_to(eq1c, LEFT)
eq_group = VGroup(eq1a, eq2a)
braces = Brace(eq_group, LEFT)
eq_text = braces.get_text("A pair of equations")
self.play(Write(eq1a))
self.play(Write(eq1b))
self.play(Write(eq1c))
self.play(Write(eq2a))
self.play(Write(eq2b))
self.play(Write(eq2c))
self.play(GrowFromCenter(braces), Write(eq_text))
self.wait(3)
def add_T_label(self, x_val, side=RIGHT, label=None, color=WHITE, animated=False, **kwargs):
"""
This method adds to the Scene:
-- a Vertical line from the x-axis to the corresponding point on the graph/curve.
-- a small vertical Triangle whose top point lies on the base of the vertical line
-- a TexMobject to be a label for the Line and Triangle, at the bottom of the Triangle.
The scene needs to have the graph have the identifier/variable name self.v_graph.
Parameters
----------
x_val (Union[float, int])
The x value at which the secant enters, and intersects
the graph for the first time.
side (np.ndarray())
label (str)
The label to give the vertline and triangle
color (str)
The hex color of the label.
animated (bool=False)
Whether or not to animate the addition of the T_label
**kwargs
Any valid keyword argument of a self.play call.
"""
triangle = RegularPolygon(n=3, start_angle=np.pi / 2)
triangle.set_height(MED_SMALL_BUFF)
triangle.move_to(self.coords_to_point(x_val, 0), UP)
triangle.set_fill(color, 1)
triangle.set_stroke(width=0)
if label is None:
T_label = TexMobject(self.variable_point_label, fill_color=color)
else:
T_label = TexMobject(label, fill_color=color)
T_label.next_to(triangle, DOWN)
v_line = self.get_vertical_line_to_graph(
x_val, self.v_graph,
color=YELLOW
)
if animated:
self.play(
DrawBorderThenFill(triangle),
ShowCreation(v_line),
Write(T_label, run_time=1),
**kwargs
)
if np.all(side == LEFT):
self.left_T_label_group = VGroup(T_label, triangle)
self.left_v_line = v_line
self.add(self.left_T_label_group, self.left_v_line)
elif np.all(side == RIGHT):
self.right_T_label_group = VGroup(T_label, triangle)
self.right_v_line = v_line
self.add(self.right_T_label_group, self.right_v_line)
def get_graph_label(
self,
graph,
label="f(x)",
x_val=None,
direction=RIGHT,
buff=MED_SMALL_BUFF,
color=None,
):
label = TexMobject(label)
color = color or graph.get_color()
label.set_color(color)
if x_val is None:
# Search from right to left
for x in np.linspace(self.x_max, self.x_min, 100):
point = self.input_to_graph_point(x, graph)
if point[1] < FRAME_Y_RADIUS:
break
x_val = x
label.next_to(
self.input_to_graph_point(x_val, graph),
direction,
buff=buff
)
label.shift_onto_screen()
return label
def get_subdivision_braces_and_labels(self,
parts,
labels,
direction,
buff=SMALL_BUFF,
min_num_quads=1):
label_mobs = VGroup()
braces = VGroup()
for label, part in zip(labels, parts):
brace = Brace(part,
direction,
min_num_quads=min_num_quads,
buff=buff)
if isinstance(label, Mobject):
label_mob = label
else:
label_mob = TexMobject(label)
label_mob.scale(self.default_label_scale_val)
label_mob.next_to(brace, direction, buff)
braces.add(brace)
label_mobs.add(label_mob)
parts.braces = braces
parts.labels = label_mobs
parts.label_kwargs = {
"labels": label_mobs.copy(),
"direction": direction,
"buff": buff,
}
return VGroup(parts.braces, parts.labels)
def get_subdivision_braces_and_labels(
self, parts, labels, direction,
buff=SMALL_BUFF,
min_num_quads=1
):
label_mobs = VGroup()
braces = VGroup()
for label, part in zip(labels, parts):
brace = Brace(
part, direction,
min_num_quads=min_num_quads,
buff=buff
)
if isinstance(label, Mobject):
label_mob = label
else:
label_mob = TexMobject(label)
label_mob.scale(self.default_label_scale_val)
label_mob.next_to(brace, direction, buff)
braces.add(brace)
label_mobs.add(label_mob)
parts.braces = braces
parts.labels = label_mobs
parts.label_kwargs = {
"labels": label_mobs.copy(),
"direction": direction,
"buff": buff,
}
return VGroup(parts.braces, parts.labels)
def get_vector_label(self, vector, label,
at_tip=False,
direction="left",
rotate=False,
color=None,
label_scale_factor=VECTOR_LABEL_SCALE_FACTOR):
if not isinstance(label, TexMobject):
if len(label) == 1:
label = "\\vec{\\textbf{%s}}" % label
label = TexMobject(label)
if color is None:
color = vector.get_color()
label.set_color(color)
label.scale(label_scale_factor)
label.add_background_rectangle()
if at_tip:
vect = vector.get_vector()
vect /= get_norm(vect)
label.next_to(vector.get_end(), vect, buff=SMALL_BUFF)
else:
angle = vector.get_angle()
if not rotate:
label.rotate(-angle, about_point=ORIGIN)
if direction == "left":
label.shift(-label.get_bottom() + 0.1 * UP)
else:
label.shift(-label.get_top() + 0.1 * DOWN)
label.rotate(angle, about_point=ORIGIN)
label.shift((vector.get_end() - vector.get_start()) / 2)
return label
def add_T_label(self,
x_val,
side=RIGHT,
label=None,
color=WHITE,
animated=False,
**kwargs):
triangle = RegularPolygon(n=3, start_angle=np.pi / 2)
triangle.set_height(MED_SMALL_BUFF)
triangle.move_to(self.coords_to_point(x_val, 0), UP)
triangle.set_fill(color, 1)
triangle.set_stroke(width=0)
if label is None:
T_label = TexMobject(self.variable_point_label, fill_color=color)
else:
T_label = TexMobject(label, fill_color=color)
T_label.next_to(triangle, DOWN)
v_line = self.get_vertical_line_to_graph(x_val,
self.v_graph,
color=YELLOW)
if animated:
self.play(DrawBorderThenFill(triangle), ShowCreation(v_line),
Write(T_label, run_time=1), **kwargs)
if np.all(side == LEFT):
self.left_T_label_group = VGroup(T_label, triangle)
self.left_v_line = v_line
self.add(self.left_T_label_group, self.left_v_line)
elif np.all(side == RIGHT):
self.right_T_label_group = VGroup(T_label, triangle)
self.right_v_line = v_line
self.add(self.right_T_label_group, self.right_v_line)
def add_axes(self):
x_axis = Line(self.tick_width * LEFT / 2, self.width * RIGHT)
y_axis = Line(MED_LARGE_BUFF * DOWN, self.height * UP)
ticks = VGroup()
heights = np.linspace(0, self.height, self.n_ticks + 1)
values = np.linspace(0, self.max_value, self.n_ticks + 1)
for y, value in zip(heights, values):
tick = Line(LEFT, RIGHT)
tick.set_width(self.tick_width)
tick.move_to(y * UP)
ticks.add(tick)
y_axis.add(ticks)
self.add(x_axis, y_axis)
self.x_axis, self.y_axis = x_axis, y_axis
if self.label_y_axis:
labels = VGroup()
for tick, value in zip(ticks, values):
label = TexMobject(str(np.round(value, 2)))
label.set_height(self.y_axis_label_height)
label.next_to(tick, LEFT, SMALL_BUFF)
labels.add(label)
self.y_axis_labels = labels
self.add(labels)
def get_coordinate_labels(self, *numbers):
# TODO: Should merge this with the code from NumberPlane.get_coordinate_labels
result = VGroup()
if len(numbers) == 0:
numbers = list(range(-int(self.x_radius), int(self.x_radius) + 1))
numbers += [
complex(0, y) for y in range(-int(self.y_radius),
int(self.y_radius) + 1) if y != 0
]
for number in numbers:
# if number == complex(0, 0):
# continue
point = self.number_to_point(number)
num_str = str(number).replace("j", "i")
if num_str.startswith("0"):
num_str = "0"
elif num_str in ["1i", "-1i"]:
num_str = num_str.replace("1", "")
num_mob = TexMobject(num_str)
num_mob.add_background_rectangle()
num_mob.set_height(self.written_coordinate_height)
num_mob.next_to(point, DOWN + LEFT, SMALL_BUFF)
result.add(num_mob)
self.coordinate_labels = result
return result
def get_vector_label(self,
vector,
label,
at_tip=False,
direction="left",
rotate=False,
color=None,
label_scale_factor=VECTOR_LABEL_SCALE_FACTOR):
if not isinstance(label, TexMobject):
if len(label) == 1:
label = "\\vec{\\textbf{%s}}" % label
label = TexMobject(label)
if color is None:
color = vector.get_color()
label.set_color(color)
label.scale(label_scale_factor)
label.add_background_rectangle()
if at_tip:
vect = vector.get_vector()
vect /= get_norm(vect)
label.next_to(vector.get_end(), vect, buff=SMALL_BUFF)
else:
angle = vector.get_angle()
if not rotate:
label.rotate(-angle, about_point=ORIGIN)
if direction == "left":
label.shift(-label.get_bottom() + 0.1 * UP)
else:
label.shift(-label.get_top() + 0.1 * DOWN)
label.rotate(angle, about_point=ORIGIN)
label.shift((vector.get_end() - vector.get_start()) / 2)
return label
def get_axis_label(self, label_tex, axis, edge, direction, buff=MED_SMALL_BUFF):
label = TexMobject(label_tex)
label.next_to(
axis.get_edge_center(edge), direction,
buff=buff
)
label.shift_onto_screen(buff=MED_SMALL_BUFF)
return label
def get_graph_label(
self,
graph,
label="f(x)",
x_val=None,
direction=RIGHT,
buff=MED_SMALL_BUFF,
color=None,
):
"""
This method returns a properly positioned label for the passed graph,
styled with the passed parameters.
Parameters
----------
graph : ParametricFunction
The curve of the function plotted.
label : str = "f(x)"
The label for the function's curve.
x_val : Union[float, int]
The x_value with which the label should be aligned.
direction : Union[np.ndarray,list,tuple]=RIGHT
The position, relative to the curve that the label will be at.
e.g LEFT, RIGHT
buff : Union[float, int]
The buffer space between the curve and the label
color : str
The color of the label.
Returns
-------
TexMobject
The LaTeX of the passed 'label' parameter
"""
label = TexMobject(label)
color = color or graph.get_color()
label.set_color(color)
if x_val is None:
# Search from right to left
for x in np.linspace(self.x_max, self.x_min, 100):
point = self.input_to_graph_point(x, graph)
if point[1] < FRAME_Y_RADIUS:
break
x_val = x
label.next_to(
self.input_to_graph_point(x_val, graph),
direction,
buff=buff
)
label.shift_onto_screen()
return label
def get_vector_label(self,
vector,
label,
at_tip=False,
direction="left",
rotate=False,
color=None,
label_scale_factor=VECTOR_LABEL_SCALE_FACTOR):
"""
Returns naming labels for the passed vector.
Parameters
----------
vector
Vector Object for which to get the label.
at_tip (bool)
Whether or not to place the label at the tip of the vector.
direction (str="left")
If the label should be on the "left" or right of the vector.
rotate (bool=False)
Whether or not to rotate it to align it with the vector.
color (str)
The color to give the label.
label_scale_factor (Union[int,float])
How much to scale the label by.
Returns
-------
TexMobject
The TexMobject of the label.
"""
if not isinstance(label, TexMobject):
if len(label) == 1:
label = "\\vec{\\textbf{%s}}" % label
label = TexMobject(label)
if color is None:
color = vector.get_color()
label.set_color(color)
label.scale(label_scale_factor)
label.add_background_rectangle()
if at_tip:
vect = vector.get_vector()
vect /= get_norm(vect)
label.next_to(vector.get_end(), vect, buff=SMALL_BUFF)
else:
angle = vector.get_angle()
if not rotate:
label.rotate(-angle, about_point=ORIGIN)
if direction == "left":
label.shift(-label.get_bottom() + 0.1 * UP)
else:
label.shift(-label.get_top() + 0.1 * DOWN)
label.rotate(angle, about_point=ORIGIN)
label.shift((vector.get_end() - vector.get_start()) / 2)
return label
def get_number_mob(self, num):
result = VGroup()
place = 0
max_place = self.max_place
while place < max_place:
digit = TexMobject(str(self.get_place_num(num, place)))
if place >= len(self.digit_place_colors):
self.digit_place_colors += self.digit_place_colors
digit.set_color(self.digit_place_colors[place])
digit.scale(self.num_scale_factor)
digit.next_to(result, LEFT, buff=SMALL_BUFF, aligned_edge=DOWN)
result.add(digit)
place += 1
return result
def get_number_mob(self, num):
result = VGroup()
place = 0
max_place = self.max_place
while place < max_place:
digit = TexMobject(str(self.get_place_num(num, place)))
if place >= len(self.digit_place_colors):
self.digit_place_colors += self.digit_place_colors
digit.set_color(self.digit_place_colors[place])
digit.scale(self.num_scale_factor)
digit.next_to(result, LEFT, buff=SMALL_BUFF, aligned_edge=DOWN)
result.add(digit)
place += 1
return result
def get_axis_labels(self, x_label="x", y_label="y"):
x_axis, y_axis = self.get_axes().split()
quads = [
(x_axis, x_label, UP, RIGHT),
(y_axis, y_label, RIGHT, UP),
]
labels = VGroup()
for axis, tex, vect, edge in quads:
label = TexMobject(tex)
label.add_background_rectangle()
label.next_to(axis, vect)
label.to_edge(edge)
labels.add(label)
self.axis_labels = labels
return labels
def get_det_text(matrix, determinant=None, background_rect=False, initial_scale_factor=2):
parens = TexMobject("(", ")")
parens.scale(initial_scale_factor)
parens.stretch_to_fit_height(matrix.get_height())
l_paren, r_paren = parens.split()
l_paren.next_to(matrix, LEFT, buff=0.1)
r_paren.next_to(matrix, RIGHT, buff=0.1)
det = TextMobject("det")
det.scale(initial_scale_factor)
det.next_to(l_paren, LEFT, buff=0.1)
if background_rect:
det.add_background_rectangle()
det_text = VGroup(det, l_paren, r_paren)
if determinant is not None:
eq = TexMobject("=")
eq.next_to(r_paren, RIGHT, buff=0.1)
result = TexMobject(str(determinant))
result.next_to(eq, RIGHT, buff=0.2)
det_text.add(eq, result)
return det_text
def get_det_text(matrix, determinant=None, background_rect=False, initial_scale_factor=2):
parens = TexMobject("(", ")")
parens.scale(initial_scale_factor)
parens.stretch_to_fit_height(matrix.get_height())
l_paren, r_paren = parens.split()
l_paren.next_to(matrix, LEFT, buff=0.1)
r_paren.next_to(matrix, RIGHT, buff=0.1)
det = TextMobject("det")
det.scale(initial_scale_factor)
det.next_to(l_paren, LEFT, buff=0.1)
if background_rect:
det.add_background_rectangle()
det_text = VGroup(det, l_paren, r_paren)
if determinant is not None:
eq = TexMobject("=")
eq.next_to(r_paren, RIGHT, buff=0.1)
result = TexMobject(str(determinant))
result.next_to(eq, RIGHT, buff=0.2)
det_text.add(eq, result)
return det_text
def get_coordinate_labels(self, x_vals=None, y_vals=None):
coordinate_labels = VGroup()
if x_vals is None:
x_vals = list(range(-int(self.x_radius), int(self.x_radius) + 1))
if y_vals is None:
y_vals = list(range(-int(self.y_radius), int(self.y_radius) + 1))
for index, vals in enumerate([x_vals, y_vals]):
num_pair = [0, 0]
for val in vals:
if val == 0:
continue
num_pair[index] = val
point = self.coords_to_point(*num_pair)
num = TexMobject(str(val))
num.add_background_rectangle()
num.set_height(self.written_coordinate_height)
num.next_to(point, DOWN + LEFT, buff=SMALL_BUFF)
coordinate_labels.add(num)
self.coordinate_labels = coordinate_labels
return coordinate_labels
def construct(self):
self.setup_axes(animate=True)
func_graph = self.get_graph(self.func_to_graph, color=RED)
func_graph2 = self.get_graph(self.func_to_graph2)
vert_line = self.get_vertical_line_to_graph(TAU,
func_graph,
color=YELLOW)
graph_lab = self.get_graph_label(func_graph, label=r"\cos(x)")
graph_lab2 = self.get_graph_label(func_graph2,
label=r"\sin(x)",
x_val=-10,
direction=LEFT)
two_pi = TexMobject(r"x = 2 \pi")
label_coord = self.input_to_graph_point(TAU, func_graph)
two_pi.next_to(label_coord, RIGHT + UP)
self.play(ShowCreation(func_graph), ShowCreation(func_graph2))
self.play(ShowCreation(vert_line), ShowCreation(graph_lab),
ShowCreation(graph_lab2), ShowCreation(two_pi))
self.wait(2)
def add_bars(self, values):
buff = float(self.width) / (2 * len(values) + 1)
bars = VGroup()
for i, value in enumerate(values):
bar = Rectangle(
height=(value / self.max_value) * self.height,
width=buff,
stroke_width=self.bar_stroke_width,
fill_opacity=self.bar_fill_opacity,
)
bar.move_to((2 * i + 1) * buff * RIGHT, DOWN + LEFT)
bars.add(bar)
bars.set_color_by_gradient(*self.bar_colors)
bar_labels = VGroup()
for bar, name in zip(bars, self.bar_names):
label = TexMobject(str(name))
label.scale(self.bar_label_scale_val)
label.next_to(bar, DOWN, SMALL_BUFF)
bar_labels.add(label)
self.add(bars, bar_labels)
self.bars = bars
self.bar_labels = bar_labels
def add_bars(self, values):
buff = float(self.width) / (2 * len(values) + 1)
bars = VGroup()
for i, value in enumerate(values):
bar = Rectangle(
height=(value / self.max_value) * self.height,
width=buff,
stroke_width=self.bar_stroke_width,
fill_opacity=self.bar_fill_opacity,
)
bar.move_to((2 * i + 1) * buff * RIGHT, DOWN + LEFT)
bars.add(bar)
bars.set_color_by_gradient(*self.bar_colors)
bar_labels = VGroup()
for bar, name in zip(bars, self.bar_names):
label = TexMobject(str(name))
label.scale(self.bar_label_scale_val)
label.next_to(bar, DOWN, SMALL_BUFF)
bar_labels.add(label)
self.add(bars, bar_labels)
self.bars = bars
self.bar_labels = bar_labels
