From de348f09b3e0e040465328ba36c425ac3f55cd0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Galip=20=C3=9Cmit=20Yolcu?=
 <galip.uemit.yolcu@hhi.fraunhofer.de>
Date: Fri, 9 Aug 2024 19:21:24 +0200
Subject: [PATCH] TRAK wrapper initial code

---
 quanda/explainers/wrappers/trak.py | 73 ++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 quanda/explainers/wrappers/trak.py

diff --git a/quanda/explainers/wrappers/trak.py b/quanda/explainers/wrappers/trak.py
new file mode 100644
index 00000000..e500fc23
--- /dev/null
+++ b/quanda/explainers/wrappers/trak.py
@@ -0,0 +1,73 @@
+from trak import TRAKer
+from trak.projectors import BasicProjector, CudaProjector, NoOpProjector
+from trak.projectors import ProjectionType
+
+from typing import Literal, Optional, Union
+import os
+import torch
+
+from quanda.explainers import BaseExplainer
+
+TRAKProjectorLiteral=Literal["cuda", "noop", "basic"]
+TRAKProjectionTypeLiteral=Literal["rademacher", "normal"]
+
+class TRAK(BaseExplainer):
+    def __init__(
+        self,
+        model: torch.nn.Module,
+        model_id: str,
+        cache_dir: Optional[str],
+        train_dataset: torch.utils.data.Dataset,
+        device: Union[str, torch.device],
+        projector: TRAKProjectorLiteral="basic",
+        proj_dim: int=128,
+        proj_type: TRAKProjectionTypeLiteral="normal",
+        seed: int=42,
+        batch_size: int=32,
+    ):
+        super(TRAK, self).__init__(model=model, train_dataset=train_dataset, model_id=model_id, cache_dir=cache_dir, device=device)
+        self.dataset=train_dataset
+        self.batch_size=batch_size
+        proj_type=ProjectionType.normal if proj_type=="normal" else ProjectionType.rademacher
+        
+        number_of_params=0
+        for p in list(self.model.sim_parameters()):
+            nn = 1
+            for s in list(p.size()):
+                nn = nn * s
+            number_of_params += nn
+        
+        projector_cls = {
+            "cuda": CudaProjector,
+            "basic": BasicProjector,
+            "noop": NoOpProjector
+        }
+        
+        projector_kwargs={
+            "grad_dim": number_of_params,
+            "proj_dim": proj_dim,
+            "proj_type": proj_type,
+            "seed": seed,
+            "device": device     
+        }
+        projector=projector_cls[projector](**projector_kwargs)
+        self.traker = TRAKer(model=model, task='image_classification', train_set_size=len(train_dataset),
+                             projector=projector, proj_dim=proj_dim, projector_seed=seed, save_dir=cache_dir)
+
+        #Train the TRAK explainer: featurize the training data
+        ld=torch.utils.data.DataLoader(self.dataset, batch_size=self.batch_size)
+        self.traker.load_checkpoint(self.model.state_dict(),model_id=0)
+        for (i,(x,y)) in enumerate(iter(ld)):
+            batch=x.to(self.device), y.to(self.device)
+            self.traker.featurize(batch=batch,inds=torch.tensor([i*self.batch_size+j for j in range(self.batch_size)]))
+        self.traker.finalize_features()
+
+    def explain(self, x, targets):
+        x=x.to(self.device)
+        self.traker.start_scoring_checkpoint(model_id=0,
+                                             checkpoint=self.model.state_dict(),
+                                             exp_name='test',
+                                            num_targets=x.shape[0])
+        self.traker.score(batch=(x,targets), num_samples=x.shape[0])
+        return torch.from_numpy(self.traker.finalize_scores(exp_name='test')).T.to(self.device)
+