Fix bug in :meth:vector_coordinate_label and move it to :class:~.geometry.py (#1407)

* remove vector_coordinate_label, move to geometry.py, fix bug

* black

* documentation and example

* apply suggestions from code review

Co-authored-by: Benjamin Hackl <[email protected]>

Author: hydrobeam

manim/mobject/geometry.py

@@ -1293,6 +1293,58 @@ def __init__(self, direction=RIGHT, buff=0, **kwargs):
             direction = np.append(np.array(direction), 0)
         Arrow.__init__(self, ORIGIN, direction, buff=buff, **kwargs)
 
+    def coordinate_label(
+        self, integer_labels: bool = True, n_dim: int = 2, color: str = WHITE
+    ):
+        """Creates a label based on the coordinates of the vector.
+
+        Parameters
+        ----------
+        integer_labels
+            Whether or not to round the coordinates to integers.
+        n_dim
+            The number of dimensions of the vector.
+        color
+            The color of the label.
+
+        Examples
+        --------
+
+        .. manim VectorCoordinateLabel
+            :save_last_frame:
+
+            class VectorCoordinateLabel(Scene):
+                def construct(self):
+                    plane = NumberPlane()
+
+                    vect_1 = Vector([1, 2])
+                    vect_2 = Vector([-3, -2])
+                    label_1 = vect1.coordinate_label()
+                    label_2 = vect2.coordinate_label(color=YELLOW)
+
+                    self.add(plane, vect_1, vect_2, label_1, label_2)
+        """
+        # avoiding circular imports
+        from .matrix import Matrix
+
+        vect = np.array(self.get_end())
+        if integer_labels:
+            vect = np.round(vect).astype(int)
+        vect = vect[:n_dim]
+        vect = vect.reshape((n_dim, 1))
+
+        label = Matrix(vect)
+        label.scale(LARGE_BUFF - 0.2)
+
+        shift_dir = np.array(self.get_end())
+        if shift_dir[0] >= 0:  # Pointing right
+            shift_dir -= label.get_left() + DEFAULT_MOBJECT_TO_MOBJECT_BUFFER * LEFT
+        else:  # Pointing left
+            shift_dir -= label.get_right() + DEFAULT_MOBJECT_TO_MOBJECT_BUFFER * RIGHT
+        label.shift(shift_dir)
+        label.set_color(color)
+        return label
+
 
 class DoubleArrow(Arrow):
     """An arrow with tips on both ends.

manim/mobject/matrix.py

@@ -31,7 +31,6 @@ def construct(self):
     "MobjectMatrix",
     "matrix_to_tex_string",
     "matrix_to_mobject",
-    "vector_coordinate_label",
     "get_det_text",
 ]
 
@@ -45,8 +44,6 @@ def construct(self):
 from ..mobject.types.vectorized_mobject import VGroup, VMobject
 from ..utils.color import WHITE
 
-VECTOR_LABEL_SCALE_FACTOR = 0.8
-
 
 def matrix_to_tex_string(matrix):
     matrix = np.array(matrix).astype("str")
@@ -63,27 +60,6 @@ def matrix_to_mobject(matrix):
     return MathTex(matrix_to_tex_string(matrix))
 
 
-def vector_coordinate_label(vector_mob, integer_labels=True, n_dim=2, color=WHITE):
-    vect = np.array(vector_mob.get_end())
-    if integer_labels:
-        vect = np.round(vect).astype(int)
-    vect = vect[:n_dim]
-    vect = vect.reshape((n_dim, 1))
-    label = Matrix(vect, add_background_rectangles_to_entries=True)
-    label.scale(VECTOR_LABEL_SCALE_FACTOR)
-
-    shift_dir = np.array(vector_mob.get_end())
-    if shift_dir[0] >= 0:  # Pointing right
-        shift_dir -= label.get_left() + DEFAULT_MOBJECT_TO_MOBJECT_BUFFER * LEFT
-    else:  # Pointing left
-        shift_dir -= label.get_right() + DEFAULT_MOBJECT_TO_MOBJECT_BUFFER * RIGHT
-    label.shift(shift_dir)
-    label.set_color(color)
-    label.rect = BackgroundRectangle(label)
-    label.add_to_back(label.rect)
-    return label
-
-
 class Matrix(VMobject):
     """A mobject that displays a matrix on the screen."""
 

manim/scene/vector_space_scene.py

@@ -14,7 +14,7 @@
 from ..constants import *
 from ..mobject.coordinate_systems import Axes, NumberPlane
 from ..mobject.geometry import Arrow, Dot, Line, Rectangle, Vector
-from ..mobject.matrix import VECTOR_LABEL_SCALE_FACTOR, Matrix, vector_coordinate_label
+from ..mobject.matrix import Matrix
 from ..mobject.mobject import Mobject
 from ..mobject.svg.tex_mobject import MathTex, Tex
 from ..mobject.types.vectorized_mobject import VGroup, VMobject
@@ -172,7 +172,7 @@ def write_vector_coordinates(self, vector, **kwargs):
             The arrow representing the vector.
 
         **kwargs
-            Any valid keyword arguments of :meth:`~.matrix.vector_coordinate_label`:
+            Any valid keyword arguments of :meth:`~.geometry.Vector.coordinate_label`:
 
             integer_labels : :class:`bool`
                 Whether or not to round the coordinates to integers. Default: ``True``.
@@ -186,7 +186,7 @@ def write_vector_coordinates(self, vector, **kwargs):
         :class:`.Matrix`
             The column matrix representing the vector.
         """
-        coords = vector_coordinate_label(vector, **kwargs)
+        coords = vector.coordinate_label(**kwargs)
         self.play(Write(coords))
         return coords
 
@@ -251,7 +251,7 @@ def get_vector_label(
         direction="left",
         rotate=False,
         color=None,
-        label_scale_factor=VECTOR_LABEL_SCALE_FACTOR,
+        label_scale_factor=LARGE_BUFF - 0.2,
     ):
         """
         Returns naming labels for the passed vector.
@@ -433,7 +433,7 @@ def vector_to_coords(self, vector, integer_labels=True, clean_up=True):
         else:
             arrow = Vector(vector)
             show_creation = True
-        array = vector_coordinate_label(arrow, integer_labels=integer_labels)
+        array = arrow.coordinate_label(integer_labels=integer_labels)
         x_line = Line(ORIGIN, vector[0] * RIGHT)
         y_line = Line(x_line.get_end(), arrow.get_end())
         x_line.set_color(X_COLOR)