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55 lines
1.4 KiB
Python
55 lines
1.4 KiB
Python
# abstractions2 goes from back to front, here we will go from front to back
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# *****
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# 0. Load mnist on the device
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from tinygrad.nn.datasets import mnist
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X_train, Y_train, _, _ = mnist()
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X_train = X_train.float()
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X_train -= X_train.mean()
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# *****
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# 1. Define an MNIST model.
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from tinygrad import Tensor
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l1 = Tensor.kaiming_uniform(128, 784)
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l2 = Tensor.kaiming_uniform(10, 128)
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def model(x): return x.flatten(1).dot(l1.T).relu().dot(l2.T)
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l1n, l2n = l1.numpy(), l2.numpy()
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# *****
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# 2. Choose a batch for training and do the backward pass.
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from tinygrad.nn.optim import SGD
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optim = SGD([l1, l2])
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Tensor.training = True
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X, Y = X_train[(samples:=Tensor.randint(128, high=X_train.shape[0]))], Y_train[samples]
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optim.zero_grad()
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model(X).sparse_categorical_crossentropy(Y).backward()
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optim.schedule_step() # this will step the optimizer without running realize
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# *****
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# 3. Create a schedule (linear uop).
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# The weight Tensors have been assigned to, but not yet realized. Everything is still lazy at this point
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# l1.uop and l2.uop define a computation graph
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from tinygrad.engine.realize import run_linear
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linear = Tensor.schedule_linear(l1, l2)
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print(f"The schedule contains {len(linear.src)} items.")
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for call in linear.src: print(str(call)[:80])
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# *****
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# 4. Lower and run the schedule (linear uop).
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run_linear(linear)
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# *****
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# 5. Print the weight change
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print("first weight change\n", l1.numpy()-l1n)
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print("second weight change\n", l2.numpy()-l2n)
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