1 files changed, 87 insertions, 0 deletions
diff --git a/examples/iris/iris_deep_to_wide.py b/examples/iris/iris_deep_to_wide.py
new file mode 100644
index 0000000..d94cce7
--- /dev/null
+++ b/examples/iris/iris_deep_to_wide.py
@@ -0,0 +1,87 @@
+import torch, torch.nn as nn
+from sklearn.datasets import load_iris
+from sklearn.preprocessing import StandardScaler
+from torch.utils.data import DataLoader, TensorDataset
+
+class Deep_Block(nn.Module):
+    def __init__(self):
+        super().__init__()
+        self.fc1 = nn.Linear(4, 1)
+        self.fc2 = nn.Linear(1, 3, bias=False)
+        
+    def forward(self, x_s):
+        x, s = x_s
+        z = torch.relu(self.fc1(x))
+        ds = self.fc2(z)
+        return (x, s + ds)
+
+class Deep_Iris_MLP(nn.Module):
+    def __init__(self, num_blocks):
+        super().__init__()
+        self.blocks = nn.Sequential(*[Deep_Block() for _ in range(num_blocks)])
+        self.final_bias = nn.Parameter(torch.zeros(3))
+
+    def forward(self, x):
+        s = torch.zeros(x.shape[0], 3, device=x.device)
+        _, final_s = self.blocks((x, s))
+        return final_s + self.final_bias
+
+class Wide_Iris_MLP(nn.Module):
+    def __init__(self, deep_net):
+        super().__init__()
+        num_neurons = len(deep_net.blocks)
+        self.layers = nn.Sequential(
+            nn.Linear(4, num_neurons),
+            nn.ReLU(),
+            nn.Linear(num_neurons, 3),
+        )
+        with torch.no_grad():
+            w1_all = []
+            b1_all = []
+            w2_all = []
+            
+            for block in deep_net.blocks:
+                w1_all.append(block.fc1.weight.data)
+                b1_all.append(block.fc1.bias.data)
+                w2_all.append(block.fc2.weight.data)
+                
+            self.layers[0].weight.copy_(torch.cat(w1_all, dim=0)) # pyright: ignore
+            self.layers[0].bias.copy_(torch.cat(b1_all, dim=0)) # pyright: ignore
+            self.layers[2].weight.copy_(torch.cat(w2_all, dim=1)) # pyright: ignore
+            self.layers[2].bias.copy_(deep_net.final_bias.data) # pyright: ignore
+
+    def forward(self, x):
+        return self.layers(x)
+
+iris = load_iris()
+scaler = StandardScaler()
+X = scaler.fit_transform(iris.data).astype('float32') # pyright: ignore
+y = iris.target.astype('int64') # pyright: ignore
+
+dataset = TensorDataset(torch.from_numpy(X), torch.from_numpy(y))
+trainloader = DataLoader(dataset, batch_size=16, shuffle=True)
+
+def train_deep_model(name: str, num_blocks):
+    net = Deep_Iris_MLP(num_blocks=num_blocks)
+    loss_fn = nn.CrossEntropyLoss()
+    optimizer = torch.optim.Adam(net.parameters(), lr=1e-2)
+
+    print(f"Training {name} ({num_blocks} blocks)...")
+    for epoch in range(100):
+        global loss
+        for inputs, targets in trainloader:
+            optimizer.zero_grad()
+            outputs = net(inputs)
+            loss = loss_fn(outputs, targets)
+            loss.backward()
+            optimizer.step()
+        if (epoch + 1) % 10 == 0:
+            print(f"  Epoch {epoch+1}, Loss: {loss.item():.4f}")
+    return net
+
+if __name__ == "__main__":
+    torch_net_a = train_deep_model("Deep Network", 10).eval()
+    torch_net_b = Wide_Iris_MLP(torch_net_a).eval()
+    
+    torch.onnx.export(torch_net_a, (torch.randn(1, 4),), "iris_a.onnx")
+    torch.onnx.export(torch_net_b, (torch.randn(1, 4),), "iris_b.onnx")