made moving-point-on-a-curve faster

proposed by empet on the forum

Author: Coding-with-Adam

doc/python/animations.md

@@ -145,9 +145,7 @@ fig.show()
 
 ```python
 import plotly.graph_objects as go
-
 import numpy as np
-
 # Generate curve data
 t = np.linspace(-1, 1, 100)
 x = t + t ** 2
@@ -156,7 +154,7 @@ xm = np.min(x) - 1.5
 xM = np.max(x) + 1.5
 ym = np.min(y) - 1.5
 yM = np.max(y) + 1.5
-N = 50
+N = 25
 s = np.linspace(-1, 1, N)
 xx = s + s ** 2
 yy = s - s ** 2
@@ -167,26 +165,29 @@ fig = go.Figure(
     data=[go.Scatter(x=x, y=y,
                      mode="lines",
                      line=dict(width=2, color="blue")),
-          go.Scatter(x=x, y=y,
-                     mode="lines",
-                     line=dict(width=2, color="blue"))],
-    layout=go.Layout(
+          go.Scatter(x=[xx[0]], y=[yy[0]],
+                     mode="markers",
+                     marker=dict(color="red", size=10))])
+fig.update_layout(width=600, height=450,
         xaxis=dict(range=[xm, xM], autorange=False, zeroline=False),
         yaxis=dict(range=[ym, yM], autorange=False, zeroline=False),
-        title_text="Kinematic Generation of a Planar Curve", hovermode="closest",
-        updatemenus=[dict(type="buttons",
-                          buttons=[dict(label="Play",
-                                        method="animate",
-                                        args=[None])])]),
-    frames=[go.Frame(
-        data=[go.Scatter(
-            x=[xx[k]],
-            y=[yy[k]],
-            mode="markers",
-            marker=dict(color="red", size=10))])
-
-        for k in range(N)]
-)
+        title_text="Kinematic Generation of a Planar Curve", title_x=0.5, 
+        updatemenus = [dict(type = "buttons",
+        buttons = [
+            dict(
+                args = [None, {"frame": {"duration": 10, "redraw": False},
+                                "fromcurrent": True, "transition": {"duration": 10}}],
+                label = "Play",
+                method = "animate",
+                 
+                )])])
+       
+fig.update(frames=[go.Frame(
+                        data=[go.Scatter(
+                                   x=[xx[k]],
+                                   y=[yy[k]])],
+                        traces=[1]) # fig.data[1] is updated by each frame
+        for k in range(N)])
 
 fig.show()
 ```