Update Tutorials 0.2 (#490)

pina/problem/zoo/supervised_problem.py

@@ -2,7 +2,7 @@
 
 from ..abstract_problem import AbstractProblem
 from ... import Condition
-from ... import Graph
+from ... import LabelTensor
 
 
 class SupervisedProblem(AbstractProblem):
@@ -22,16 +22,22 @@ class SupervisedProblem(AbstractProblem):
 
     conditions = {}
     output_variables = None
+    input_variables = None
 
-    def __init__(self, input_, output_):
+    def __init__(
+        self, input_, output_, input_variables=None, output_variables=None
+    ):
         """
         Initialize the SupervisedProblem class.
 
         :param input_: Input data of the problem.
+        :type input_: torch.Tensor | LabelTensor | Graph | Data
         :param output_: Output data of the problem.
-        :type output_: torch.Tensor | Graph
+        :type output_: torch.Tensor | LabelTensor | Graph | Data
         """
-        if isinstance(input_, Graph):
-            input_ = input_.data
+        # Set input and output variables
+        self.input_variables = input_variables
+        self.output_variables = output_variables
+        # Set the condition
         self.conditions["data"] = Condition(input=input_, target=output_)
         super().__init__()