Simu: Let Signal have default final positions

simulations/lib/signals/digitisedsignal.py

@@ -1,4 +1,5 @@
 #!/usr/bin/env python3
+
 import numpy as np
 import scipy.interpolate as interp
 
@@ -14,7 +15,7 @@ class DigitisedSignal(Signal):
     Model an arbitrary digitised signal that can be translated to another position and time.
     """
 
-    def __init__(self, signal, sample_rate, t_0 = 0, x_0 = 0, periodic=True, interp1d_kw = None, velocity=None):
+    def __init__(self, signal, sample_rate, t_0 = 0, x_0 = 0, periodic=True, interp1d_kw = None, velocity=None, t_f = None, x_f = None):
         """
         Initialise by saving the raw signal
 
@@ -37,8 +38,12 @@ class DigitisedSignal(Signal):
             Dictionary will be entered in as **kwargs.
         velocity : float, optional
             Defaults to the speed of light in m/s.
+        t_f : float, optional
+            Default time that this signal is received.
+        x_f : float, optional
+            Default Location that this signal is received.
         """
-        super().__init__(t_0=t_0, x_0=x_0, velocity=velocity)
+        super().__init__(t_0=t_0, x_0=x_0, velocity=velocity, t_f=t_f, x_f=x_f)
 
         self.raw = np.asarray(signal)
         self.periodic = periodic

simulations/lib/signals/signal.py

@@ -11,7 +11,7 @@ class Signal():
 
     Super object, cannot be used directly.
     """
-    def __init__(self, t_0 = 0, x_0 = 0, velocity=None):
+    def __init__(self, t_0 = 0, x_0 = 0, velocity=None, t_f = None, x_f = None):
         """
         Parameters
         ----------
@@ -21,12 +21,27 @@ class Signal():
             Location that this signal is sent out from.
         velocity : float, optional
             Defaults to the speed of light in m/s.
+        t_f : float, optional
+            Default time that this signal is received.
+        x_f : float, optional
+            Default Location that this signal is received.
         """
+        if t_0 is None:
+            raise ValueError("t_0 cannot be None")
+        if x_0 is None:
+            raise ValueError("x_0 cannot be None")
+
+        self.x_0 = np.asarray(x_0) # m
+        self.t_0 = np.asarray(t_0) # s
 
         self.velocity = 299792458 if velocity is None else velocity # m / s
 
-        self.x_0 = x_0 # m
-        self.t_0 = t_0 # s
+        # Default final positions
+        t_f = np.asarray(t_f) if t_f is not None else None
+        x_f = np.asarray(x_f) if x_f is not None else None
+
+        self.x_f = x_f
+        self.t_f = t_f
 
     def __call__(self, t_f = None, x_f = None, **kwargs):
         """
@@ -43,7 +58,7 @@ class Signal():
 
         raise NotImplementedError
 
-    def spatial_time_offset(self, x_f, x_0=None, velocity=None):
+    def spatial_time_offset(self, x_f=None, x_0=None, velocity=None):
         """
         Calculate the time offset caused by a spatial distance.
         """
@@ -52,15 +67,27 @@ class Signal():
 
         if x_0 is None:
             x_0 = self.x_0
+        if x_f is None:
+            x_f = self.x_f
+
+        ## make sure they are arrays
+        x_0 = np.asarray(x_0) if x_0 is not None else None
+        x_f = np.asarray(x_f) if x_f is not None else None
 
         return np.sqrt( np.sum((x_f - x_0)**2, axis=-1) )/velocity
 
-    def temporal_time_offset(self, t_f, t_0=None):
+    def temporal_time_offset(self, t_f=None, t_0=None):
         """
         Calculate the time offset caused by a temporal distance.
         """
         if t_0 is None:
             t_0 = self.t_0
+        if t_f is None:
+            t_f = self.t_f
+
+        ## make sure they are arrays
+        t_0 = np.asarray(t_0) if t_0 is not None else None
+        t_f = np.asarray(t_f) if t_f is not None else None
 
         return t_f - t_0
 
@@ -76,26 +103,35 @@ class Signal():
         Returns:
          the time shift
         """
+        # Get default values
+        ## starting point
+        if t_0 is None:
+            t_0 = self.t_0
+        if x_0 is None:
+            x_0 = self.x_0
 
-        ## spatial offset
+        ## final point
+        if x_f is None:
+            x_f = self.x_f
+        if t_f is None:
+            t_f = self.t_f
+
+        ## make sure they are arrays
+        t_0 = np.asarray(t_0) if t_0 is not None else None
+        x_0 = np.asarray(x_0) if x_0 is not None else None
+        t_f = np.asarray(t_f) if t_f is not None else None
+        x_f = np.asarray(x_f) if x_f is not None else None
+
+        # spatial offset
         if x_f is None:
             spatial_time_offset = 0
         else:
-            x_f = np.asarray(x_f)
-            if x_0 is None:
-                x_0 = self.x_0
-
             spatial_time_offset = self.spatial_time_offset(x_f, x_0=x_0, velocity=velocity)
 
-        ## temporal offset
+        # temporal offset
         if t_f is None:
             temporal_time_offset = 0
         else:
-            t_f = np.asarray(t_f)
-
-            if t_0 is None:
-                t_0 = self.t_0
-
             temporal_time_offset = self.temporal_time_offset(t_f, t_0=t_0)
 
         return temporal_time_offset - spatial_time_offset