add package problems

problems/function_fitting/sin.py

@@ -0,0 +1,14 @@
+import numpy as np
+
+from . import FunctionFittingProblem
+
+
+class Sin(FunctionFittingProblem):
+    def __init__(self, size=100):
+        self.num_inputs = 1
+        self.num_outputs = 1
+        self.batch = size
+        self.inputs = np.linspace(0, np.pi, self.batch)[:, None]
+        self.target = np.sin(self.inputs)
+        print(self.inputs, self.target)
+        super().__init__(self.num_inputs, self.num_outputs, self.batch, self.inputs, self.target)