matplotlib · timhoffm · Oct 8, 2018 · Mar 9, 2018 · Mar 9, 2018 · Mar 10, 2018
diff --git a/doc/users/whats_new.rst b/doc/users/whats_new.rst
@@ -192,6 +192,15 @@ and the title will not be moved via this algorithm.
 
 
 
+Adjusted ``matplotlib.widgets.Slider`` to have vertical orientation
+-------------------------------------------------------------------
+
+The :class:`matplotlib.widgets.Slider` widget now takes an optional argument
+``orientation`` which indicates the direction (``'horizontal'`` or
+``'vertical'``) that the slider should take.
+
+
+
 New convenience methods for GridSpec
 ------------------------------------
 

diff --git a/lib/matplotlib/tests/test_widgets.py b/lib/matplotlib/tests/test_widgets.py
@@ -319,6 +319,20 @@ def test_slider_valmin_valmax():
     assert slider.val == slider.valmax
 
 
+def test_slider_horizontal_vertical():
+    fig, ax = plt.subplots()
+    slider = widgets.Slider(ax=ax, label='', valmin=0.0, valmax=24.0,
+                            valinit=12.0, orientation='horizontal')
+    slider.set_val(10.0)
+    assert slider.val == 10.0
+
+    fig, ax = plt.subplots()
+    slider = widgets.Slider(ax=ax, label='', valmin=0.0, valmax=24.0,
+                            valinit=12.0, orientation='vertical')
+    slider.set_val(10.0)
+    assert slider.val == 10.0
+
+
 def check_polygon_selector(event_sequence, expected_result, selections_count):
     """Helper function to test Polygon Selector
 

diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
@@ -268,7 +268,8 @@ class Slider(AxesWidget):
     """
     def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
                  closedmin=True, closedmax=True, slidermin=None,
-                 slidermax=None, dragging=True, valstep=None, **kwargs):
+                 slidermax=None, dragging=True, valstep=None,
+                 orientation='horizontal', **kwargs):
         """
         Parameters
         ----------
@@ -310,6 +311,9 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
         valstep : float, optional, default: None
             If given, the slider will snap to multiples of `valstep`.
 
+        orientation : str, 'horizontal' or 'vertical', default: 'horizontal'
+            The orientation of the slider.
+
         Notes
         -----
         Additional kwargs are passed on to ``self.poly`` which is the
@@ -325,6 +329,11 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
         if slidermax is not None and not hasattr(slidermax, 'val'):
             raise ValueError("Argument slidermax ({}) has no 'val'"
                              .format(type(slidermax)))
+        if orientation not in ['horizontal', 'vertical']:
+            raise ValueError("Argument orientation ({}) must be either"
+                             "'horizontal' or 'vertical'".format(orientation))
+
+        self.orientation = orientation
         self.closedmin = closedmin
         self.closedmax = closedmax
         self.slidermin = slidermin
@@ -338,27 +347,44 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
             valinit = valmin
         self.val = valinit
         self.valinit = valinit
-        self.poly = ax.axvspan(valmin, valinit, 0, 1, **kwargs)
-        self.vline = ax.axvline(valinit, 0, 1, color='r', lw=1)
+        if orientation == 'vertical':
+            self.poly = ax.axhspan(valmin, valinit, 0, 1, **kwargs)
+            self.hline = ax.axhline(valinit, 0, 1, color='r', lw=1)
+        else:
+            self.poly = ax.axvspan(valmin, valinit, 0, 1, **kwargs)
+            self.vline = ax.axvline(valinit, 0, 1, color='r', lw=1)
 
         self.valfmt = valfmt
         ax.set_yticks([])
-        ax.set_xlim((valmin, valmax))
+        if orientation == 'vertical':
+            ax.set_ylim((valmin, valmax))
+        else:
+            ax.set_xlim((valmin, valmax))
         ax.set_xticks([])
         ax.set_navigate(False)
 
         self.connect_event('button_press_event', self._update)
         self.connect_event('button_release_event', self._update)
         if dragging:
             self.connect_event('motion_notify_event', self._update)
-        self.label = ax.text(-0.02, 0.5, label, transform=ax.transAxes,
-                             verticalalignment='center',
-                             horizontalalignment='right')
+        if orientation == 'vertical':
+            self.label = ax.text(0.5, 1.02, label, transform=ax.transAxes,
+                                 verticalalignment='bottom',
+                                 horizontalalignment='center')
+
+            self.valtext = ax.text(0.5, -0.02, valfmt % valinit,
+                                   transform=ax.transAxes,
+                                   verticalalignment='top',
+                                   horizontalalignment='center')
+        else:
+            self.label = ax.text(-0.02, 0.5, label, transform=ax.transAxes,
+                                 verticalalignment='center',
+                                 horizontalalignment='right')
 
-        self.valtext = ax.text(1.02, 0.5, valfmt % valinit,
-                               transform=ax.transAxes,
-                               verticalalignment='center',
-                               horizontalalignment='left')
+            self.valtext = ax.text(1.02, 0.5, valfmt % valinit,
+                                   transform=ax.transAxes,
+                                   verticalalignment='center',
+                                   horizontalalignment='left')
 
         self.cnt = 0
         self.observers = {}
@@ -412,7 +438,10 @@ def _update(self, event):
             self.drag_active = False
             event.canvas.release_mouse(self.ax)
             return
-        val = self._value_in_bounds(event.xdata)
+        if self.orientation == 'vertical':
+            val = self._value_in_bounds(event.ydata)
+        else:
+            val = self._value_in_bounds(event.xdata)
         if val not in [None, self.val]:
             self.set_val(val)
 
@@ -425,8 +454,12 @@ def set_val(self, val):
         val : float
         """
         xy = self.poly.xy
-        xy[2] = val, 1
-        xy[3] = val, 0
+        if self.orientation == 'vertical':
+            xy[1] = 0, val
+            xy[2] = 1, val
+        else:
+            xy[2] = val, 1
+            xy[3] = val, 0
         self.poly.xy = xy
         self.valtext.set_text(self.valfmt % val)
         if self.drawon: