Invert experimental import logic to opt-in (#651)

* Invert experimental import logic to opt-in

* remove default user import

ocpmodels/common/utils.py

@@ -264,22 +264,31 @@ def _import_local_file(path: Path, *, project_root: Path) -> None:
 
 
 def setup_experimental_imports(project_root: Path) -> None:
-    experimental_folder = (project_root / "experimental").resolve()
-    if not experimental_folder.exists() or not experimental_folder.is_dir():
+    """
+    Import selected directories of modules from the "experimental" subdirectory.
+
+    If a file named ".include" is present in the "experimental" subdirectory,
+    this will be read as a list of experimental subdirectories whose module
+    (including in any subsubdirectories) should be imported.
+
+    :param project_root: The root directory of the project (i.e., the "ocp" folder)
+    """
+    experimental_dir = (project_root / "experimental").resolve()
+    if not experimental_dir.exists() or not experimental_dir.is_dir():
         return
 
-    experimental_files = [
-        f.resolve().absolute() for f in experimental_folder.rglob("*.py")
-    ]
-    # Ignore certain directories within experimental
-    ignore_file = experimental_folder / ".ignore"
-    if ignore_file.exists():
-        with open(ignore_file, "r") as f:
-            for line in f.read().splitlines():
-                for ignored_file in (experimental_folder / line).rglob("*.py"):
-                    experimental_files.remove(
-                        ignored_file.resolve().absolute()
-                    )
+    experimental_files = []
+    include_file = experimental_dir / ".include"
+
+    if include_file.exists():
+        with open(include_file, "r") as f:
+            include_dirs = f.read().splitlines()
+
+        for inc_dir in include_dirs:
+            experimental_files.extend(
+                f.resolve().absolute()
+                for f in (experimental_dir / inc_dir).rglob("*.py")
+            )
 
     for f in experimental_files:
         _import_local_file(f, project_root=project_root)
@@ -313,7 +322,7 @@ def setup_imports(config: Optional[dict] = None) -> None:
     from ocpmodels.common.registry import registry
 
     skip_experimental_imports = (config or {}).get(
-        "skip_experimental_imports", None
+        "skip_experimental_imports", False
     )
 
     # First, check if imports are already setup
@@ -1159,11 +1168,11 @@ def get_commit_hash():
     return commit_hash
 
 
-def cg_change_mat(l, device="cpu"):
-    if l not in [2]:
+def cg_change_mat(ang_mom: int, device: str = "cpu") -> torch.tensor:
+    if ang_mom not in [2]:
         raise NotImplementedError
 
-    if l == 2:
+    if ang_mom == 2:
         change_mat = torch.tensor(
             [
                 [3 ** (-0.5), 0, 0, 0, 3 ** (-0.5), 0, 0, 0, 3 ** (-0.5)],
@@ -1192,12 +1201,14 @@ def cg_change_mat(l, device="cpu"):
     return change_mat
 
 
-def irreps_sum(l):
+def irreps_sum(ang_mom: int) -> int:
     """
-    Returns the sum of the dimensions of the irreps up to the specified l.
+    Returns the sum of the dimensions of the irreps up to the specified angular momentum.
+
+    :param ang_mom: max angular momenttum to sum up dimensions of irreps
     """
     total = 0
-    for i in range(l + 1):
+    for i in range(ang_mom + 1):
         total += 2 * i + 1
 
     return total