def init_points(self):
start_angle = np.pi / 2 + self.arc_angle / 2
end_angle = np.pi / 2 - self.arc_angle / 2
self.add(Arc(start_angle=start_angle, angle=-self.arc_angle))
tick_angle_range = np.linspace(start_angle, end_angle, self.num_ticks)
for index, angle in enumerate(tick_angle_range):
vect = rotate_vector(RIGHT, angle)
tick = Line((1 - self.tick_length) * vect, vect)
label = TexMobject(str(10 * index))
label.set_height(self.tick_length)
label.shift((1 + self.tick_length) * vect)
self.add(tick, label)
needle = Polygon(LEFT,
UP,
RIGHT,
stroke_width=0,
fill_opacity=1,
fill_color=self.needle_color)
needle.stretch_to_fit_width(self.needle_width)
needle.stretch_to_fit_height(self.needle_height)
needle.rotate(start_angle - np.pi / 2, about_point=ORIGIN)
self.add(needle)
self.needle = needle
self.center_offset = self.get_center()
def generate_points(self):
start_angle = np.pi / 2 + self.arc_angle / 2
end_angle = np.pi / 2 - self.arc_angle / 2
self.add(Arc(
start_angle=start_angle,
angle=-self.arc_angle
))
tick_angle_range = np.linspace(start_angle, end_angle, self.num_ticks)
for index, angle in enumerate(tick_angle_range):
vect = rotate_vector(RIGHT, angle)
tick = Line((1 - self.tick_length) * vect, vect)
label = TexMobject(str(10 * index))
label.set_height(self.tick_length)
label.shift((1 + self.tick_length) * vect)
self.add(tick, label)
needle = Polygon(
LEFT, UP, RIGHT,
stroke_width=0,
fill_opacity=1,
fill_color=self.needle_color
)
needle.stretch_to_fit_width(self.needle_width)
needle.stretch_to_fit_height(self.needle_height)
needle.rotate(start_angle - np.pi / 2, about_point=ORIGIN)
self.add(needle)
self.needle = needle
self.center_offset = self.get_center()
def get_tex(self,
tex,
scale=1,
buff=1,
invert_dir=False,
invert_texto=False,
remove_rot=True,
**moreargs):
linea_referencia = Line(self[0][0].get_start(), self[0][-1].get_end())
texto = TexMobject(tex, **moreargs)
ancho = texto.get_height() / 2
if invert_texto:
inv = PI
else:
inv = 0
if remove_rot:
texto.scale(scale).move_to(self)
else:
texto.rotate(
linea_referencia.get_angle()).scale(scale).move_to(self)
texto.rotate(inv)
if invert_dir:
inv = -1
else:
inv = 1
texto.shift(self.direccion * (buff + 1) * ancho)
return texto
def add_tex(self, text, scale=1, buff=-1, **moreargs):
linea_referencia = Line(self[0][0].get_start(), self[0][-1].get_end())
texto = TexMobject(text, **moreargs)
ancho = texto.get_height() / 2
texto.rotate(linea_referencia.get_angle()).scale(scale).move_to(self)
texto.shift(self.direccion * (buff + 1) * ancho)
return self.add(texto)
def construct(self):
eq1 = TextMobject(r"$ \vec{X}_0 \cdot \vec{Y}_1 = 3 $")
eq1.shift(2 * UP)
eq2 = TexMobject(r"\vec{F}_{net} = \sum_i \vec{F}_i")
eq2.shift(2 * DOWN)
self.play(Write(eq1))
self.play(Write(eq2))
self.wait()
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_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 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 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
