Document that angles are accepted in bracket arrowstyles.

Author: QuLogic

doc/users/next_whats_new/bracket_angle.rst

@@ -0,0 +1,25 @@
+Angles on Bracket arrow styles
+------------------------------
+
+Angles specified on the *Bracket* arrow styles (``]-[``, ``]-``, ``-[``, or
+``|-|`` passed to *arrowstyle* parameter of `.FancyArrowPatch`) are now
+applied. Previously, the *angleA* and *angleB* options were allowed, but did
+nothing.
+
+.. plot::
+
+    import matplotlib.pyplot as plt
+    import matplotlib.patches as mpatches
+
+    fig, ax = plt.subplots()
+    ax.set(xlim=(0, 1), ylim=(-1, 4))
+
+    for i, stylename in enumerate((']-[', '|-|')):
+        for j, angle in enumerate([-30, 60]):
+            arrowstyle = f'{stylename},angleA={angle},angleB={-angle}'
+            patch = mpatches.FancyArrowPatch((0.1, 2*i + j), (0.9, 2*i + j),
+                                             arrowstyle=arrowstyle,
+                                             mutation_scale=25)
+            ax.text(0.5, 2*i + j, arrowstyle,
+                    verticalalignment='bottom', horizontalalignment='center')
+            ax.add_patch(patch)

lib/matplotlib/patches.py

@@ -3293,7 +3293,9 @@ def __init__(self,
                 Length of the bracket.
 
             angleA : float, default: None
-                Angle between the bracket and the line.
+                Angle, in degrees, between the bracket and the line. Zero is
+                perpendicular to the line, and positive measures
+                counterclockwise.
 
             widthB : float, default: 1.0
                 Width of the bracket.
@@ -3302,7 +3304,9 @@ def __init__(self,
                 Length of the bracket.
 
             angleB : float, default: None
-                Angle between the bracket and the line.
+                Angle, in degrees, between the bracket and the line. Zero is
+                perpendicular to the line, and positive measures
+                counterclockwise.
             """
             super().__init__(True, True,
                              widthA=widthA, lengthA=lengthA, angleA=angleA,
@@ -3343,7 +3347,9 @@ def __init__(self, widthB=1., lengthB=0.2, angleB=None):
                 Length of the bracket.
 
             angleB : float, default: None
-                Angle between the bracket and the line.
+                Angle, in degrees, between the bracket and the line. Zero is
+                perpendicular to the line, and positive measures
+                counterclockwise.
             """
             super().__init__(None, True,
                              widthB=widthB, lengthB=lengthB, angleB=angleB)
@@ -3362,13 +3368,17 @@ def __init__(self,
                 Width of the bracket.
 
             angleA : float, default: None
-                Angle between the bracket and the line.
+                Angle, in degrees, between the bracket and the line. Zero is
+                perpendicular to the line, and positive measures
+                counterclockwise.
 
             widthB : float, default: 1.0
                 Width of the bracket.
 
             angleB : float, default: None
-                Angle between the bracket and the line.
+                Angle, in degrees, between the bracket and the line. Zero is
+                perpendicular to the line, and positive measures
+                counterclockwise.
             """
             super().__init__(True, True,
                              widthA=widthA, lengthA=0, angleA=angleA,