Allow y to be a pandas dataframe or series

pysr/sr.py

@@ -957,7 +957,8 @@ class PySRRegressor(BaseEstimator, RegressorMixin):
         if len(X.shape) == 1:
             X = X[:, None]
 
-        assert not isinstance(y, pd.DataFrame)
+        if isinstance(y, pd.DataFrame) or isinstance(y, pd.Series):
+            y = np.array(y)
 
         if variable_names is None or len(variable_names) == 0:
             variable_names = [f"x{i}" for i in range(X.shape[1])]

test/test.py

@@ -143,6 +143,8 @@ class TestPipeline(unittest.TestCase):
         y = true_fn(X)
         noise = np.random.randn(500) * 0.01
         y = y + noise
+        # We also test y as a pandas array:
+        y = pd.Series(y)
         # Resampled array is a different order of features:
         Xresampled = pd.DataFrame(
             {