Add dtype parameter to External (#274)

* Add dtype parameter to External

* simplify

* cast box too

* Allow to pass dtype as a string

* Understand a 1D box as a diagonal one

* Understand box batching

* typo

* typo

* Update test

* Force static_shapes in cuda graph mode
Allow External to take kwargs for load_model

* Add some warnings

tests/test_calculator.py

@@ -12,49 +12,45 @@
 from utils import create_example_batch
 
 
-def test_compare_forward():
-    checkpoint = join(dirname(dirname(__file__)), "tests", "example.ckpt")
-    z, pos, _ = create_example_batch(multiple_batches=False)
-    calc = External(checkpoint, z.unsqueeze(0))
-    model = load_model(checkpoint, derivative=True)
-
-    e_calc, f_calc = calc.calculate(pos, None)
-    e_pred, f_pred = model(z, pos)
-
-    assert_allclose(e_calc, e_pred)
-    assert_allclose(f_calc, f_pred.unsqueeze(0))
-
 @pytest.mark.parametrize("box", [None, torch.eye(3)])
-def test_compare_forward_cuda_graph(box):
-    if not torch.cuda.is_available():
+@pytest.mark.parametrize("use_cuda_graphs", [True, False])
+def test_compare_forward(box, use_cuda_graphs):
+    if use_cuda_graphs and not torch.cuda.is_available():
         pytest.skip("CUDA not available")
     checkpoint = join(dirname(dirname(__file__)), "tests", "example.ckpt")
-    args = {"model": "tensornet",
-            "embedding_dimension": 128,
-            "num_layers": 2,
-            "num_rbf": 32,
-            "rbf_type": "expnorm",
-            "trainable_rbf": False,
-            "activation": "silu",
-            "cutoff_lower": 0.0,
-            "cutoff_upper": 5.0,
-            "max_z": 100,
-            "max_num_neighbors": 128,
-            "equivariance_invariance_group": "O(3)",
-            "prior_model": None,
-            "atom_filter": -1,
-            "derivative": True,
-            "output_model": "Scalar",
-            "reduce_op": "sum",
-            "precision": 32 }
-    model = create_model(args).to(device="cuda")
+    args = {
+        "model": "tensornet",
+        "embedding_dimension": 128,
+        "num_layers": 2,
+        "num_rbf": 32,
+        "rbf_type": "expnorm",
+        "trainable_rbf": False,
+        "activation": "silu",
+        "cutoff_lower": 0.0,
+        "cutoff_upper": 5.0,
+        "max_z": 100,
+        "max_num_neighbors": 128,
+        "equivariance_invariance_group": "O(3)",
+        "prior_model": None,
+        "atom_filter": -1,
+        "derivative": True,
+        "output_model": "Scalar",
+        "reduce_op": "sum",
+        "precision": 32,
+    }
+    device = "cpu" if not use_cuda_graphs else "cuda"
+    model = create_model(args).to(device=device)
     z, pos, _ = create_example_batch(multiple_batches=False)
-    z = z.to("cuda")
-    pos = pos.to("cuda")
-    calc = External(checkpoint, z.unsqueeze(0), use_cuda_graph=False, device="cuda")
-    calc_graph = External(checkpoint, z.unsqueeze(0), use_cuda_graph=True, device="cuda")
+    z = z.to(device)
+    pos = pos.to(device)
+    calc = External(checkpoint, z.unsqueeze(0), use_cuda_graph=False, device=device)
+    calc_graph = External(
+        checkpoint, z.unsqueeze(0), use_cuda_graph=use_cuda_graphs, device=device
+    )
     calc.model = model
     calc_graph.model = model
+    if box is not None:
+        box = (box * 2 * args["cutoff_upper"]).unsqueeze(0)
     for _ in range(10):
         e_calc, f_calc = calc.calculate(pos, box)
         e_pred, f_pred = calc_graph.calculate(pos, box)

torchmdnet/calculators.py

@@ -4,6 +4,7 @@
 
 import torch
 from torchmdnet.models.model import load_model
+import warnings
 
 # dict of preset transforms
 tranforms = {
@@ -42,6 +43,10 @@ class External:
         Whether to use CUDA graphs to speed up the calculation. Default: False
     cuda_graph_warmup_steps : int, optional
         Number of steps to run as warmup before recording the CUDA graph. Default: 12
+    dtype : torch.dtype or str, optional
+        Cast the input to this dtype if defined. If passed as a string it should be a valid torch dtype. Default: torch.float32
+    kwargs : dict, optional
+        Extra arguments to pass to the model when loading it.
     """
 
     def __init__(
@@ -52,10 +57,28 @@ def __init__(
         output_transform=None,
         use_cuda_graph=False,
         cuda_graph_warmup_steps=12,
+        dtype=torch.float32,
+        **kwargs,
     ):
         if isinstance(netfile, str):
-            self.model = load_model(netfile, device=device, derivative=True)
+            extra_args = kwargs
+            if use_cuda_graph:
+                warnings.warn(
+                    "CUDA graphs are enabled, setting static_shapes=True and check_errors=False"
+                )
+                extra_args["static_shapes"] = True
+                extra_args["check_errors"] = False
+            self.model = load_model(
+                netfile,
+                device=device,
+                derivative=True,
+                **extra_args,
+            )
         elif isinstance(netfile, torch.nn.Module):
+            if kwargs:
+                warnings.warn(
+                    "Warning: extra arguments are being ignored when passing a torch.nn.Module"
+                )
             self.model = netfile
         else:
             raise ValueError(
@@ -87,6 +110,12 @@ def __init__(
         self.forces = None
         self.box = None
         self.pos = None
+        if isinstance(dtype, str):
+            try:
+                dtype = getattr(torch, dtype)
+            except AttributeError:
+                raise ValueError(f"Unknown torch dtype {dtype}")
+        self.dtype = dtype
 
     def _init_cuda_graph(self):
         stream = torch.cuda.Stream()
@@ -101,7 +130,7 @@ def _init_cuda_graph(self):
                     self.embeddings, self.pos, self.batch, self.box
                 )
 
-    def calculate(self, pos, box = None):
+    def calculate(self, pos, box=None):
         """Calculate the energy and forces of the system.
 
         Parameters
@@ -118,7 +147,9 @@ def calculate(self, pos, box = None):
         forces : torch.Tensor
             Forces on the atoms in the system.
         """
-        pos = pos.to(self.device).type(torch.float32).reshape(-1, 3)
+        pos = pos.to(self.device).to(self.dtype).reshape(-1, 3)
+        if box is not None:
+            box = box.to(self.device).to(self.dtype)
         if self.use_cuda_graph:
             if self.pos is None:
                 self.pos = (
@@ -128,10 +159,12 @@ def calculate(self, pos, box = None):
                     .requires_grad_(pos.requires_grad)
                 )
             if self.box is None and box is not None:
-                self.box = box.clone().to(self.device).detach()
+                self.box = box.clone().to(self.device).to(self.dtype).detach()
             if self.cuda_graph is None:
                 self._init_cuda_graph()
-            assert self.cuda_graph is not None, "CUDA graph is not initialized. This should not had happened."
+            assert (
+                self.cuda_graph is not None
+            ), "CUDA graph is not initialized. This should not had happened."
             with torch.no_grad():
                 self.pos.copy_(pos)
                 if box is not None: