Fix bugs

xautodl/datasets/math_adv_funcs.py

@@ -64,65 +64,29 @@ class ComposedSinFunc(FitFunc):
         )
 
 
-class ComposedSinFuncV2(FitFunc):
+class ComposedCosFunc(FitFunc):
     """The composed sin function that outputs:
-      f(x) = amplitude-scale-of(x) * sin( period-phase-shift-of(x) )
-    - the amplitude scale is a quadratic function of x
-    - the period-phase-shift is another quadratic function of x
+    f(x) = a * cos( b*x ) + c
     """
 
-    def __init__(self, **kwargs):
-        super(ComposedSinFuncV2, self).__init__(0, None)
-        self.fit(**kwargs)
+    def __init__(self, params, xstr="x"):
+        super(ComposedCosFunc, self).__init__(3, None, params, xstr)
 
     def __call__(self, x):
         self.check_valid()
-        scale = self._params["amplitude_scale"](x)
-        period_phase = self._params["period_phase_shift"](x)
-        return scale * math.sin(period_phase)
-
-    def fit(self, **kwargs):
-        num_sin_phase = kwargs.get("num_sin_phase", 7)
-        sin_speed_use_power = kwargs.get("sin_speed_use_power", True)
-        min_amplitude = kwargs.get("min_amplitude", 1)
-        max_amplitude = kwargs.get("max_amplitude", 4)
-        phase_shift = kwargs.get("phase_shift", 0.0)
-        # create parameters
-        if kwargs.get("amplitude_scale", None) is None:
-            amplitude_scale = QuadraticFunc(
-                [(0, min_amplitude), (0.5, max_amplitude), (1, min_amplitude)]
-            )
-        else:
-            amplitude_scale = kwargs.get("amplitude_scale")
-        if kwargs.get("period_phase_shift", None) is None:
-            fitting_data = []
-            if sin_speed_use_power:
-                temp_max_scalar = 2 ** (num_sin_phase - 1)
-            else:
-                temp_max_scalar = num_sin_phase - 1
-            for i in range(num_sin_phase):
-                if sin_speed_use_power:
-                    value = (2 ** i) / temp_max_scalar
-                    next_value = (2 ** (i + 1)) / temp_max_scalar
-                else:
-                    value = i / temp_max_scalar
-                    next_value = (i + 1) / temp_max_scalar
-                for _phase in (0, 0.25, 0.5, 0.75):
-                    inter_value = value + (next_value - value) * _phase
-                    fitting_data.append((inter_value, math.pi * (2 * i + _phase)))
-            period_phase_shift = QuarticFunc(fitting_data)
-        else:
-            period_phase_shift = kwargs.get("period_phase_shift")
-        self.set(
-            dict(amplitude_scale=amplitude_scale, period_phase_shift=period_phase_shift)
-        )
+        a = self._params[0]
+        b = self._params[1]
+        c = self._params[2]
+        return a * math.cos(b * x) + c
 
     def _getitem(self, x, weights):
         raise NotImplementedError
 
     def __repr__(self):
-        return "{name}({amplitude_scale} * sin({period_phase_shift}))".format(
+        return "{name}({a} * sin({b} * {x}) + {c})".format(
             name=self.__class__.__name__,
-            amplitude_scale=self._params["amplitude_scale"],
-            period_phase_shift=self._params["period_phase_shift"],
+            a=self._params[0],
+            b=self._params[1],
+            c=self._params[2],
+            x=self.xstr,
         )