Add ramping without initial value

moreauga · moreauga · commit 09eec91b97af · 2025-10-13T17:39:17.000-07:00
From Avikar's edits to CL's labscript
diff --git a/labscript/functions.py b/labscript/functions.py
@@ -36,6 +36,13 @@ def ramp(duration, initial, final):
     m = (final - initial)/duration
     return lambda t: m*t + initial
 
+def ramp_without_initial(duration, final):
+    """
+    GM copied from AP 04/27/2022
+    allows ramping without having to keep track of last value of ramp  
+    """
+    return lambda initial: ramp(duration, initial, final)
+
 def sine(duration, amplitude, angfreq, phase, dc_offset):
     """Defines a sine wave.
 
diff --git a/labscript/outputs.py b/labscript/outputs.py
@@ -301,6 +301,23 @@ def do_checks(self, trigger_times):
         Raises:
             LabscriptError: If a trigger time conflicts with an instruction.
         """
+        
+        ### Resolve Ramps - Added 04/27/2022 GM, copied from - AP
+        instruction_by_time = sorted(self.instructions.items())
+        for i, (time, instruction) in enumerate(instruction_by_time):
+            if isinstance(instruction, dict):
+                if 'initial' in instruction['description']:
+                    if i == 0:
+                        print("Don't begin with a ramp without an initial value.")
+                    else:
+                        previous_instruction = instruction_by_time[i - 1][1]
+                        #### Is the previous instruction a ramp
+                        if isinstance(previous_instruction, dict):
+                            self.instructions[time]['function'] = instruction['function'](previous_instruction['final'])
+                        #### Is the previous instruction a constant
+                        else:
+                            self.instructions[time]['function'] = instruction['function'](previous_instruction)
+                            
         # Check if there are no instructions. Generate a warning and insert an
         # instruction telling the output to remain at its default value.
         if not self.instructions:
@@ -589,19 +606,36 @@ def ramp(self, t, duration, initial, final, samplerate, units=None, truncation=1
                         "output.\n"
                     )
             else:
-                self.add_instruction(
-                    t,
-                    {
-                        "function": functions.ramp(
-                            round(t + duration, 10) - round(t, 10), initial, final
-                        ),
-                        "description": "linear ramp",
-                        "initial time": t,
-                        "end time": t + truncation * duration,
-                        "clock rate": samplerate,
-                        "units": units,
-                    }
-                )
+                if initial == None:
+                    self.add_instruction(
+                        t, 
+                        {
+                            'function': functions.ramp_without_initial(
+                                round(t + duration, 10) - round(t, 10), final
+                            ), 
+                            'description': 'linear ramp without initial',
+                            'initial time': t,
+                            'end time': t + truncation * duration, 
+                            'clock rate': samplerate, 
+                            'units': units, 
+                            'final': final
+                        }
+                    )
+                else:
+                    self.add_instruction(
+                        t,
+                        {
+                            "function": functions.ramp(
+                                round(t + duration, 10) - round(t, 10), initial, final
+                            ),
+                            "description": "linear ramp",
+                            "initial time": t,
+                            "end time": t + truncation * duration,
+                            "clock rate": samplerate,
+                            "units": units,
+                            'final': final
+                        }
+                    )
         return truncation * duration
 
     def sine(
