Add function input error handling

backend/src/manager.py

@@ -4,7 +4,12 @@ import matplotlib.lines as mlines
 import matplotlib.pyplot as plt
 import numpy as np
 from matplotlib.figure import Figure
-from sympy import sympify
+from sympy import sympify, symbols, sin, cos, exp
+from sympy.parsing.sympy_parser import (
+  standard_transformations, 
+  implicit_multiplication_application, 
+  parse_expr,
+)
 
 from logic import (
     DataGenerationOptions,
@@ -75,10 +80,31 @@ class Manager:
         y_col: int,
     ) -> Dataset:
         if dataset_type == "Generate":
+            x1, x2 = symbols("x1 x2")
+            allowed_locals = {
+                "x1": x1,
+                "x2": x2,
+                "sin": sin,
+                "cos": cos,
+                "exp": exp,
+            }
+            if not function.strip():
+                raise ValueError("Function cannot be empty")
+
             try:
-                parsed_function = sympify(function)
+                parsed_function = parse_expr(
+                    function, 
+                    local_dict=allowed_locals,
+                    transformations=standard_transformations + (implicit_multiplication_application,),
+                    evaluate=True,
+                )
             except Exception as e:
-                raise ValueError(f"Invalid function {e}")
+                raise ValueError(f"Invalid function: {e}")
+
+            unknown_symbols = parsed_function.free_symbols - {x1, x2}
+            if unknown_symbols:
+                unknown_names = ", ".join(sorted(str(s) for s in unknown_symbols))
+                raise ValueError(f"Unknown variable(s): {unknown_names}. Allowed: x1, x2")
 
             x1_range = self._parse_range(x1_range_input)
             x2_range = self._parse_range(x2_range_input)

frontends/gradio/main.py

@@ -71,26 +71,30 @@ def handle_generate_plots(
     w2_range_input: str,
     resolution: int,
 ) -> tuple[Manager, Figure, Figure, Figure]:
-    return manager.handle_generate_plots(
-        dataset_type,
-        function,
-        x1_range_input,
-        x2_range_input,
-        x_selection_method,
-        sigma,
-        nsample,
-        csv_file,
-        has_header,
-        x1_col,
-        x2_col,
-        y_col,
-        loss_type,
-        regularizer_type,
-        reg_levels_input,
-        w1_range_input,
-        w2_range_input,
-        resolution,
-    )
+    try:
+        return manager.handle_generate_plots(
+            dataset_type,
+            function,
+            x1_range_input,
+            x2_range_input,
+            x_selection_method,
+            sigma,
+            nsample,
+            csv_file,
+            has_header,
+            x1_col,
+            x2_col,
+            y_col,
+            loss_type,
+            regularizer_type,
+            reg_levels_input,
+            w1_range_input,
+            w2_range_input,
+            resolution,
+        )
+    except Exception as e:
+        raise gr.Error("Error generating plots: " + str(e))
+
 
 def handle_use_suggested_settings(
     manager: Manager,
@@ -107,20 +111,23 @@ def handle_use_suggested_settings(
     x2_col: int,
     y_col: int,
 ) -> tuple[Manager, str, str, str]:
-    return manager.handle_use_suggested_settings(
-        dataset_type,
-        function,
-        x1_range_input,
-        x2_range_input,
-        x_selection_method,
-        sigma,
-        nsample,
-        csv_file,
-        has_header,
-        x1_col,
-        x2_col,
-        y_col,
-    )
+    try:
+        return manager.handle_use_suggested_settings(
+            dataset_type,
+            function,
+            x1_range_input,
+            x2_range_input,
+            x_selection_method,
+            sigma,
+            nsample,
+            csv_file,
+            has_header,
+            x1_col,
+            x2_col,
+            y_col,
+        )
+    except Exception as e:
+        raise gr.Error("Error computing suggested settings: " + str(e))
 
 
 def launch():