Time Windowing for Time Response Plots

docs/user_guide/tutorial_analyses_part_2.ipynb

@@ -4663,7 +4663,47 @@
     "\n",
     "- `.plot_2d()`: plot orbit of a selected node of a rotor system.\n",
     "\n",
-    "- `.plot_3d()`: plot orbits for each node on the rotor system in a 3D view."
+    "- `.plot_3d()`: plot orbits for each node on the rotor system in a 3D view.\n",
+    "\n",
+    "The plotting methods can also select a time window without rerunning the simulation. The limits are given in seconds and are applied to the stored response after `run_time_response()` finishes.\n",
+    "\n",
+    "For a regular time window, provide both `t_initial` and `t_final`:\n",
+    "\n",
+    "```python\n",
+    "response3.plot_1d(\n",
+    "    probe=[probe1, probe2],\n",
+    "    t_initial=4.0,\n",
+    "    t_final=8.0,\n",
+    ")\n",
+    "\n",
+    "response3.plot_2d(\n",
+    "    node=26,\n",
+    "    t_initial=4.0,\n",
+    "    t_final=8.0,\n",
+    ")\n",
+    "\n",
+    "response3.plot_3d(t_initial=4.0, t_final=8.0)\n",
+    "```\n",
+    "\n",
+    "Time limits can also be passed with units, for example `Q_(500, \"ms\")`.\n",
+    "\n",
+    "To select one complete cycle, use `one_cycle=True`. Because the scalar `speed` supplied to `run_time_response()` is stored in the result, the known rotor speed is used to determine the period:\n",
+    "\n",
+    "```python\n",
+    "# Last complete cycle of the response\n",
+    "response3.plot_1d(probe=[probe1, probe2], one_cycle=True)\n",
+    "response3.plot_2d(node=26, one_cycle=True)\n",
+    "response3.plot_3d(one_cycle=True)\n",
+    "```\n",
+    "\n",
+    "A cycle can be anchored by providing only one boundary. With `t_initial`, the cycle starts at that time; with `t_final`, the cycle ends at that time:\n",
+    "\n",
+    "```python\n",
+    "response3.plot_2d(node=26, one_cycle=True, t_initial=8.0)\n",
+    "response3.plot_3d(one_cycle=True, t_final=12.0)\n",
+    "```\n",
+    "\n",
+    "Do not provide both `t_initial` and `t_final` together with `one_cycle=True`. Use a regular time window when both boundaries must be fixed explicitly."
    ]
   },
   {

ross/multi_rotor/multi_rotor.py

@@ -1050,7 +1050,7 @@ def run_time_response(self, speed, F, t, method="default", **kwargs):
         """
         if self.mesh.backlash:
             t_, yout, xout = self.time_response(speed, F, t, method=method, **kwargs)
-            results = BacklashResults(self, t, yout, xout)
+            results = BacklashResults(self, t, yout, xout, speed=speed)
         else:
             results = super().run_time_response(speed, F, t, method=method, **kwargs)
 

ross/multi_rotor/results.py

@@ -46,6 +46,8 @@ class BacklashResults(TimeResponseResults):
         System response.
     xout : array
         Time evolution of the state vector.
+    speed : float or array_like, optional
+        Rotor speed used to calculate the response, in rad/s.
 
     Attributes
     ----------
@@ -103,8 +105,8 @@ class BacklashResults(TimeResponseResults):
         },
     }
 
-    def __init__(self, rotor, t, yout, xout):
-        super().__init__(rotor, t, yout, xout)
+    def __init__(self, rotor, t, yout, xout, speed=None):
+        super().__init__(rotor, t, yout, xout, speed=speed)
 
         min_dt = np.diff(self.t).min()