Added the Player class to plotting.py

examples/player.py

+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+Created on Fri Mar 20 11:01:38 2020
+
+@author: lenz
+
+This is a simple showcase of the Player class in pyVis.plotting.
+
+Full credit goes to ImportanceOfBeingErnest from stackoverflow as this is
+copied from his answer here: https://stackoverflow.com/a/46327978.
+"""
+
+import numpy as np
+import matplotlib.pyplot as plt
+
+import pyVis
+pyVis.styling.defaultStyling()
+
+fig, ax = plt.subplots()
+x = np.linspace(0,6*np.pi, num=100)
+y = np.sin(x)
+
+ax.plot(x,y)
+point, = ax.plot([],[], marker="o", color="crimson", ms=15)
+
+def update(i):
+    point.set_data(x[i],y[i])
+
+ani = pyVis.plotting.Player(fig, update, maxi=len(y)-1)
+
+plt.show()
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plotting.py

@@ -11,6 +11,9 @@ import matplotlib.cm as cm
 from matplotlib.pyplot import figure
 from matplotlib import rcParams
 import matplotlib.pyplot as plt
+from matplotlib.animation import FuncAnimation
+import mpl_toolkits.axes_grid1
+import matplotlib.widgets
 
 from .styling import Fig,tight,newFig,ax,colors,names
 from .aux import iterTest,gaussian
@@ -879,4 +882,97 @@ def alignTicks(a1,a2,whichTicks='major',whichAxis='y',ranges='flex'):
         else:
             raise Exception('This is really weird.')
         
-    return None
\ No newline at end of file
+    return None
+
+class Player(FuncAnimation):
+    '''
+    This class sets up a simple animation with forward/backwards playing, stop
+    and stepwise increment buttons as well as a timeline.
+    Full credit goes to ImportanceOfBeingErnest from stackoverflow as this is
+    copied from his answer here: https://stackoverflow.com/a/46327978.
+    '''
+    def __init__(self, fig, func, frames=None, init_func=None, fargs=None,
+                 save_count=None, mini=0, maxi=100, pos=(0.125, 0.92), **kwargs):
+        self.i = 0
+        self.min=mini
+        self.max=maxi
+        self.runs = True
+        self.forwards = True
+        self.fig = fig
+        self.func = func
+        self.setup(pos)
+        FuncAnimation.__init__(self,self.fig, self.update, frames=self.play(), 
+                                           init_func=init_func, fargs=fargs,
+                                           save_count=save_count, **kwargs )    
+
+    def play(self):
+        while self.runs:
+            self.i = self.i+self.forwards-(not self.forwards)
+            if self.i > self.min and self.i < self.max:
+                yield self.i
+            else:
+                self.stop()
+                yield self.i
+
+    def start(self):
+        self.runs=True
+        self.event_source.start()
+
+    def stop(self, event=None):
+        self.runs = False
+        self.event_source.stop()
+
+    def forward(self, event=None):
+        self.forwards = True
+        self.start()
+    def backward(self, event=None):
+        self.forwards = False
+        self.start()
+    def oneforward(self, event=None):
+        self.forwards = True
+        self.onestep()
+    def onebackward(self, event=None):
+        self.forwards = False
+        self.onestep()
+
+    def onestep(self):
+        if self.i > self.min and self.i < self.max:
+            self.i = self.i+self.forwards-(not self.forwards)
+        elif self.i == self.min and self.forwards:
+            self.i+=1
+        elif self.i == self.max and not self.forwards:
+            self.i-=1
+        self.func(self.i)
+        self.slider.set_val(self.i)
+        self.fig.canvas.draw_idle()
+
+    def setup(self, pos):
+        playerax = self.fig.add_axes([pos[0],pos[1], 0.64, 0.04])
+        divider = mpl_toolkits.axes_grid1.make_axes_locatable(playerax)
+        bax = divider.append_axes("right", size="80%", pad=0.05)
+        sax = divider.append_axes("right", size="80%", pad=0.05)
+        fax = divider.append_axes("right", size="80%", pad=0.05)
+        ofax = divider.append_axes("right", size="100%", pad=0.05)
+        sliderax = divider.append_axes("right", size="500%", pad=0.07)
+        
+        self.button_oneback = matplotlib.widgets.Button(playerax, label=u'$\u29CF$')
+        self.button_back = matplotlib.widgets.Button(bax, label=u'$\u25C0$')
+        self.button_stop = matplotlib.widgets.Button(sax, label=u'$\u25A0$')
+        self.button_forward = matplotlib.widgets.Button(fax, label=u'$\u25B6$')
+        self.button_oneforward = matplotlib.widgets.Button(ofax, label=u'$\u29D0$')
+        
+        self.button_oneback.on_clicked(self.onebackward)
+        self.button_back.on_clicked(self.backward)
+        self.button_stop.on_clicked(self.stop)
+        self.button_forward.on_clicked(self.forward)
+        self.button_oneforward.on_clicked(self.oneforward)
+        self.slider = matplotlib.widgets.Slider(sliderax, '', 
+                                                self.min, self.max, valinit=self.i)
+        self.slider.on_changed(self.set_pos)
+
+    def set_pos(self,i):
+        self.i = int(self.slider.val)
+        self.func(self.i)
+
+    def update(self,i):
+        self.slider.set_val(i)
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