01 hotova

hod_1/data/example_pytorch.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+import argparse
+
+import torch
+import torchmetrics
+
+import npfl138
+from npfl138.datasets.mnist import MNIST
+npfl138.require_version("2526.1")
+
+# Parse arguments
+parser = argparse.ArgumentParser()
+parser.add_argument("--batch_size", default=50, type=int, help="Batch size.")
+parser.add_argument("--epochs", default=10, type=int, help="Number of epochs.")
+parser.add_argument("--hidden_layer_size", default=100, type=int, help="Size of the hidden layer.")
+parser.add_argument("--seed", default=42, type=int, help="Random seed.")
+parser.add_argument("--threads", default=1, type=int, help="Maximum number of threads to use.")
+
+
+class Dataset(npfl138.TransformedDataset):
+    def transform(self, example):
+        image = example["image"]  # a torch.Tensor with torch.uint8 values in [0, 255] range
+        image = image.to(torch.float32) / 255  # image converted to float32 and rescaled to [0, 1]
+        label = example["label"]  # a torch.Tensor with a single integer representing the label
+        return image, label  # return an (input, target) pair
+
+
+def main(args: argparse.Namespace) -> None:
+    # Set the random seed and the number of threads.
+    npfl138.startup(args.seed, args.threads)
+    npfl138.global_keras_initializers()
+
+    # Load the data and create dataloaders.
+    mnist = MNIST()
+
+    train = torch.utils.data.DataLoader(Dataset(mnist.train), batch_size=args.batch_size, shuffle=True)
+    dev = torch.utils.data.DataLoader(Dataset(mnist.dev), batch_size=args.batch_size)
+    test = torch.utils.data.DataLoader(Dataset(mnist.test), batch_size=args.batch_size)
+
+    # Create the model.
+    model = torch.nn.Sequential(
+        torch.nn.Flatten(),
+        torch.nn.Linear(MNIST.C * MNIST.H * MNIST.W, args.hidden_layer_size),
+        torch.nn.ReLU(),
+        torch.nn.Linear(args.hidden_layer_size, MNIST.LABELS),
+    )
+    print("The following model has been created:", model)
+
+    # Create the TrainableModule and configure it for training.
+    model = npfl138.TrainableModule(model)
+
+    model.configure(
+        optimizer=torch.optim.Adam(model.parameters()),
+        loss=torch.nn.CrossEntropyLoss(),
+        metrics={"accuracy": torchmetrics.Accuracy("multiclass", num_classes=MNIST.LABELS)},
+    )
+
+    # Train the model.
+    model.fit(train, dev=dev, epochs=args.epochs)
+
+    # Evaluate the model on the test data.
+    model.evaluate(test)
+
+
+if __name__ == "__main__":
+    main_args = parser.parse_args([] if "__file__" not in globals() else None)
+    main(main_args)

hod_1/data/example_pytorch_tensorboard.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python3
+import argparse
+
+import torch
+import torchmetrics
+
+import npfl138
+from npfl138.datasets.mnist import MNIST
+npfl138.require_version("2526.1")
+
+# Parse arguments
+parser = argparse.ArgumentParser()
+parser.add_argument("--batch_size", default=50, type=int, help="Batch size.")
+parser.add_argument("--epochs", default=10, type=int, help="Number of epochs.")
+parser.add_argument("--hidden_layer_size", default=100, type=int, help="Size of the hidden layer.")
+parser.add_argument("--seed", default=42, type=int, help="Random seed.")
+parser.add_argument("--threads", default=1, type=int, help="Maximum number of threads to use.")
+
+
+class Dataset(npfl138.TransformedDataset):
+    def transform(self, example):
+        image = example["image"]  # a torch.Tensor with torch.uint8 values in [0, 255] range
+        image = image.to(torch.float32) / 255  # image converted to float32 and rescaled to [0, 1]
+        label = example["label"]  # a torch.Tensor with a single integer representing the label
+        return image, label  # return an (input, target) pair
+
+
+def main(args: argparse.Namespace) -> None:
+    # Set the random seed and the number of threads.
+    npfl138.startup(args.seed, args.threads)
+    npfl138.global_keras_initializers()
+
+    # Load the data and create dataloaders.
+    mnist = MNIST()
+
+    train = torch.utils.data.DataLoader(Dataset(mnist.train), batch_size=args.batch_size, shuffle=True)
+    dev = torch.utils.data.DataLoader(Dataset(mnist.dev), batch_size=args.batch_size)
+    test = torch.utils.data.DataLoader(Dataset(mnist.test), batch_size=args.batch_size)
+
+    # Create the model.
+    model = torch.nn.Sequential(
+        torch.nn.Flatten(),
+        torch.nn.Linear(MNIST.C * MNIST.H * MNIST.W, args.hidden_layer_size),
+        torch.nn.ReLU(),
+        torch.nn.Linear(args.hidden_layer_size, MNIST.LABELS),
+    )
+    print("The following model has been created:", model)
+
+    # Create the TrainableModule and configure it for training.
+    model = npfl138.TrainableModule(model)
+
+    model.configure(
+        optimizer=torch.optim.Adam(model.parameters()),
+        loss=torch.nn.CrossEntropyLoss(),
+        metrics={"accuracy": torchmetrics.Accuracy("multiclass", num_classes=MNIST.LABELS)},
+        logdir=npfl138.format_logdir("logs/{file-}{timestamp}{-config}", **vars(args)),
+    )
+
+    # Train the model.
+    model.fit(train, dev=dev, epochs=args.epochs, log_config=vars(args), log_graph=True)
+
+    # Evaluate the model on the test data.
+    model.evaluate(test)
+
+
+if __name__ == "__main__":
+    main_args = parser.parse_args([] if "__file__" not in globals() else None)
+    main(main_args)

hod_1/data/mnist_layers_activations.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+import argparse
+
+import torch
+import torchmetrics
+
+import npfl138
+npfl138.require_version("2526.1")
+from npfl138.datasets.mnist import MNIST
+
+parser = argparse.ArgumentParser()
+# These arguments will be set appropriately by ReCodEx, even if you change them.
+parser.add_argument("--activation", default="none", choices=["none", "relu", "tanh", "sigmoid"], help="Activation.")
+parser.add_argument("--batch_size", default=50, type=int, help="Batch size.")
+parser.add_argument("--epochs", default=10, type=int, help="Number of epochs.")
+parser.add_argument("--hidden_layer_size", default=100, type=int, help="Size of the hidden layer.")
+parser.add_argument("--hidden_layers", default=1, type=int, help="Number of layers.")
+parser.add_argument("--recodex", default=False, action="store_true", help="Evaluation in ReCodEx.")
+parser.add_argument("--seed", default=42, type=int, help="Random seed.")
+parser.add_argument("--threads", default=1, type=int, help="Maximum number of threads to use.")
+# If you add more arguments, ReCodEx will keep them with your default values.
+
+
+class Dataset(npfl138.TransformedDataset):
+    def transform(self, example):
+        image = example["image"]  # a torch.Tensor with torch.uint8 values in [0, 255] range
+        image = image.to(torch.float32) / 255  # image converted to float32 and rescaled to [0, 1]
+        label = example["label"]  # a torch.Tensor with a single integer representing the label
+        return image, label  # return an (input, target) pair
+
+
+def main(args: argparse.Namespace) -> dict[str, float]:
+    # Set the random seed and the number of threads.
+    npfl138.startup(args.seed, args.threads, args.recodex)
+    npfl138.global_keras_initializers()
+
+    # Load the data and create dataloaders.
+    mnist = MNIST()
+
+    train = torch.utils.data.DataLoader(Dataset(mnist.train), batch_size=args.batch_size, shuffle=True)
+    dev = torch.utils.data.DataLoader(Dataset(mnist.dev), batch_size=args.batch_size)
+
+    # Create the model.
+    model = torch.nn.Sequential()
+
+    # TODO: Finish the model. Namely:
+    # - start by adding the `torch.nn.Flatten()` layer;
+    # - then add `args.hidden_layers` number of fully connected hidden layers
+    #   `torch.nn.Linear()`, each with `args.hidden_layer_size` neurons and followed by
+    #   a specified `args.activation`, allowing "none", "relu", "tanh", "sigmoid";
+    # - finally, add an output fully connected layer with `MNIST.LABELS` units.
+    ...
+
+    # Create the TrainableModule and configure it for training.
+    model = npfl138.TrainableModule(model)
+
+    model.configure(
+        optimizer=torch.optim.Adam(model.parameters()),
+        loss=torch.nn.CrossEntropyLoss(),
+        metrics={"accuracy": torchmetrics.Accuracy("multiclass", num_classes=MNIST.LABELS)},
+        logdir=npfl138.format_logdir("logs/{file-}{timestamp}{-config}", **vars(args)),
+    )
+
+    # Train the model.
+    logs = model.fit(train, dev=dev, epochs=args.epochs)
+
+    # Return development metrics for ReCodEx to validate.
+    return {metric: value for metric, value in logs.items() if metric.startswith("dev:")}
+
+
+if __name__ == "__main__":
+    main_args = parser.parse_args([] if "__file__" not in globals() else None)
+    main(main_args)

hod_1/data/numpy_entropy.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+import argparse
+
+import numpy as np
+
+parser = argparse.ArgumentParser()
+# These arguments will be set appropriately by ReCodEx, even if you change them.
+parser.add_argument("--data_path", default="numpy_entropy_data.txt", type=str, help="Data distribution path.")
+parser.add_argument("--model_path", default="numpy_entropy_model.txt", type=str, help="Model distribution path.")
+parser.add_argument("--recodex", default=False, action="store_true", help="Evaluation in ReCodEx.")
+# If you add more arguments, ReCodEx will keep them with your default values.
+
+
+def main(args: argparse.Namespace) -> tuple[float, float, float]:
+    # TODO: Load data distribution, each line containing a datapoint -- a string.
+    with open(args.data_path, "r") as data:
+        for line in data:
+            line = line.rstrip("\n")
+            # TODO: Process the line, aggregating data with built-in Python
+            # data structures (not NumPy, which is not suitable for incremental
+            # addition and string mapping).
+
+    # TODO: Create a NumPy array containing the data distribution. The
+    # NumPy array should contain only data, not any mapping. Alternatively,
+    # the NumPy array might be created after loading the model distribution.
+
+    # TODO: Load model distribution, each line `string \t probability`.
+    with open(args.model_path, "r") as model:
+        for line in model:
+            line = line.rstrip("\n")
+            # TODO: Process the line, aggregating using Python data structures.
+
+    # TODO: Create a NumPy array containing the model distribution.
+
+    # TODO: Compute the entropy H(data distribution). You should not use
+    # manual for/while cycles, but instead use the fact that most NumPy methods
+    # operate on all elements (for example `*` is vector element-wise multiplication).
+    entropy = ...
+
+    # TODO: Compute cross-entropy H(data distribution, model distribution).
+    # When some data distribution elements are missing in the model distribution,
+    # the resulting crossentropy should be `np.inf`.
+    crossentropy = ...
+
+    # TODO: Compute KL-divergence D_KL(data distribution, model_distribution),
+    # again using `np.inf` when needed.
+    kl_divergence = ...
+
+    # Return the computed values for ReCodEx to validate.
+    return entropy, crossentropy, kl_divergence
+
+
+if __name__ == "__main__":
+    main_args = parser.parse_args([] if "__file__" not in globals() else None)
+    entropy, crossentropy, kl_divergence = main(main_args)
+    print(f"Entropy: {entropy:.2f} nats")
+    print(f"Crossentropy: {crossentropy:.2f} nats")
+    print(f"KL divergence: {kl_divergence:.2f} nats")

hod_1/data/numpy_entropy_data_1.txt

@@ -0,0 +1,7 @@
+A
+BB
+A
+A
+BB
+A
+CCC

hod_1/data/numpy_entropy_data_2.txt

@@ -0,0 +1,7 @@
+A
+BB
+A
+A
+BB
+A
+CCC

hod_1/data/numpy_entropy_model_1.txt

@@ -0,0 +1,3 @@
+BB	0.4
+A	0.5
+CCC	0.1

hod_1/data/numpy_entropy_model_2.txt

@@ -0,0 +1,3 @@
+BB	0.4
+A	0.5
+D	0.1

hod_1/data/numpy_entropy_model_3.txt

@@ -0,0 +1,100 @@
+ttvhw	0.0094312126288478
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+lfgnw	0.00765022250913878
+wxaxe	0.0118444674613856
+qpeyg	0.0164611528436398
+ydmkt	0.00163874437311358

hod_1/data/numpy_entropy_model_4.txt

@@ -0,0 +1,200 @@
+aysirskl	0.000465969985327225
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+syvktodv	0.0052132145962036
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hod_1/data/pca_first.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python3
+import argparse
+
+import numpy as np
+import torch
+
+import npfl138
+from npfl138.datasets.mnist import MNIST
+npfl138.require_version("2526.1")
+
+parser = argparse.ArgumentParser()
+# These arguments will be set appropriately by ReCodEx, even if you change them.
+parser.add_argument("--examples", default=256, type=int, help="MNIST examples to use.")
+parser.add_argument("--iterations", default=100, type=int, help="Iterations of the power algorithm.")
+parser.add_argument("--recodex", default=False, action="store_true", help="Evaluation in ReCodEx.")
+parser.add_argument("--seed", default=42, type=int, help="Random seed.")
+parser.add_argument("--threads", default=1, type=int, help="Maximum number of threads to use.")
+# If you add more arguments, ReCodEx will keep them with your default values.
+
+
+def main(args: argparse.Namespace) -> tuple[float, float]:
+    # Set the random seed and the number of threads.
+    npfl138.startup(args.seed, args.threads, args.recodex)
+    npfl138.global_keras_initializers()
+
+    # Prepare the data.
+    mnist = MNIST()
+
+    data_indices = np.random.choice(len(mnist.train), size=args.examples, replace=False)
+    data = mnist.train.data["images"][data_indices].to(torch.float32) / 255
+
+    # TODO: Data has shape [args.examples, MNIST.C, MNIST.H, MNIST.W].
+    # We want to reshape it to [args.examples, MNIST.C * MNIST.H * MNIST.W].
+    # We can do so using `torch.reshape(data, new_shape)` with new shape
+    # `[data.shape[0], data.shape[1] * data.shape[2] * data.shape[3]]`.
+    data = ...
+
+    # TODO: Now compute mean of every feature. Use `torch.mean`, and set
+    # `dim` (or `axis`) argument to zero -- therefore, the mean will be
+    # computed across the first dimension, so across examples.
+    #
+    # Note that for compatibility with Numpy/TF/Keras, all `dim` arguments
+    # in PyTorch can be also called `axis`.
+    mean = ...
+
+    # TODO: Compute the covariance matrix. The covariance matrix is
+    #   (data - mean)^T @ (data - mean) / data.shape[0]
+    # where transpose can be computed using `torch.transpose` or `torch.t` and
+    # matrix multiplication using either Python operator @ or `torch.matmul`.
+    cov = ...
+
+    # TODO: Compute the total variance, which is the sum of the diagonal
+    # of the covariance matrix. To extract the diagonal use `torch.diagonal`,
+    # and to sum a tensor use `torch.sum`.
+    total_variance = ...
+
+    # TODO: Now run `args.iterations` of the power iteration algorithm.
+    # Start with a vector of `cov.shape[0]` ones of type `torch.float32` using `torch.ones`.
+    v = ...
+    for i in range(args.iterations):
+        # TODO: In the power iteration algorithm, we compute
+        # 1. v = cov v
+        #    The matrix-vector multiplication can be computed as regular matrix multiplication
+        #    or using `torch.mv`.
+        # 2. s = l2_norm(v)
+        #    The l2_norm can be computed using for example `torch.linalg.vector_norm`.
+        # 3. v = v / s
+        ...
+
+    # The `v` is now approximately the eigenvector of the largest eigenvalue, `s`.
+    # We now compute the explained variance, which is the ratio of `s` and `total_variance`.
+    explained_variance = s / total_variance
+
+    # Return the total and explained variance for ReCodEx to validate
+    return total_variance, 100 * explained_variance
+
+
+if __name__ == "__main__":
+    main_args = parser.parse_args([] if "__file__" not in globals() else None)
+    total_variance, explained_variance = main(main_args)
+    print(f"Total variance: {total_variance:.2f}")
+    print(f"Explained variance: {explained_variance:.2f}%")