779 lines
26 KiB
Plaintext
Vendored
779 lines
26 KiB
Plaintext
Vendored
{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"# Tutorial: Introduction to `Trainer` class\n",
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"[](https://colab.research.google.com/github/mathLab/PINA/blob/master/tutorials/tutorial11/tutorial.ipynb)\n",
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"\n",
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"In this tutorial, we will delve deeper into the functionality of the `Trainer` class, which serves as the cornerstone for training **PINA** [Solvers](https://mathlab.github.io/PINA/_rst/_code.html#solvers). \n",
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"\n",
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"The `Trainer` class offers a plethora of features aimed at improving model accuracy, reducing training time and memory usage, facilitating logging visualization, and more thanks to the amazing job done by the PyTorch Lightning team!\n",
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"\n",
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"Our leading example will revolve around solving a simple regression problem where we want to approximate the following function with a Neural Net model $\\mathcal{M}_{\\theta}$:\n",
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"$$y = x^3$$\n",
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"by having only a set of $20$ observations $\\{x_i, y_i\\}_{i=1}^{20}$, with $x_i \\sim\\mathcal{U}[-3, 3]\\;\\;\\forall i\\in(1,\\dots,20)$.\n",
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"\n",
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"Let's start by importing useful modules!"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"try:\n",
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" import google.colab\n",
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"\n",
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" IN_COLAB = True\n",
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"except:\n",
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" IN_COLAB = False\n",
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"if IN_COLAB:\n",
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" !pip install \"pina-mathlab[tutorial]\"\n",
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"\n",
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"import torch\n",
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"import warnings\n",
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"\n",
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"from pina import Trainer\n",
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"from pina.solver import SupervisedSolver\n",
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"from pina.model import FeedForward\n",
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"from pina.problem.zoo import SupervisedProblem\n",
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"\n",
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"warnings.filterwarnings(\"ignore\")"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"Define problem and solver."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 2,
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"metadata": {},
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"outputs": [],
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"source": [
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"# defining the problem\n",
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"x_train = torch.empty((20, 1)).uniform_(-3, 3)\n",
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"y_train = x_train.pow(3) + 3 * torch.randn_like(x_train)\n",
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"\n",
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"problem = SupervisedProblem(x_train, y_train)\n",
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"\n",
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"# build the model\n",
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"model = FeedForward(\n",
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" layers=[10, 10],\n",
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" func=torch.nn.Tanh,\n",
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" output_dimensions=1,\n",
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" input_dimensions=1,\n",
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")\n",
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"\n",
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"# create the SupervisedSolver object\n",
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"solver = SupervisedSolver(problem, model, use_lt=False)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"Till now we just followed the extact step of the previous tutorials. The `Trainer` object\n",
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"can be initialized by simiply passing the `SupervisedSolver` solver"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 3,
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"metadata": {},
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"outputs": [
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"GPU available: True (mps), used: True\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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}
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],
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"source": [
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"trainer = Trainer(solver=solver)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Trainer Accelerator\n",
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"\n",
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"When creating the `Trainer`, **by default** the most performing `accelerator` for training which is available in your system will be chosen, ranked as follows:\n",
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"1. [TPU](https://cloud.google.com/tpu/docs/intro-to-tpu)\n",
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"2. [IPU](https://www.graphcore.ai/products/ipu)\n",
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"3. [HPU](https://habana.ai/)\n",
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"4. [GPU](https://www.intel.com/content/www/us/en/products/docs/processors/what-is-a-gpu.html#:~:text=What%20does%20GPU%20stand%20for,video%20editing%2C%20and%20gaming%20applications) or [MPS](https://developer.apple.com/metal/pytorch/)\n",
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"5. CPU\n",
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"\n",
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"For setting manually the `accelerator` run:\n",
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"\n",
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"* `accelerator = {'gpu', 'cpu', 'hpu', 'mps', 'cpu', 'ipu'}` sets the accelerator to a specific one"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 15,
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"metadata": {},
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"outputs": [
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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}
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],
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"source": [
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"trainer = Trainer(solver=solver, accelerator=\"cpu\")"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"As you can see, even if a `GPU` is available on the system, it is not used since we set `accelerator='cpu'`."
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Trainer Logging\n",
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"\n",
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"In **PINA** you can log metrics in different ways. The simplest approach is to use the `MetricTracker` class from `pina.callbacks`, as seen in the [*Introduction to Physics Informed Neural Networks training*](https://github.com/mathLab/PINA/blob/master/tutorials/tutorial1/tutorial.ipynb) tutorial.\n",
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"\n",
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"However, especially when we need to train multiple times to get an average of the loss across multiple runs, `lightning.pytorch.loggers` might be useful. Here we will use `TensorBoardLogger` (more on [logging](https://lightning.ai/docs/pytorch/stable/extensions/logging.html) here), but you can choose the one you prefer (or make your own one).\n",
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"\n",
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"We will now import `TensorBoardLogger`, do three runs of training, and then visualize the results. Notice we set `enable_model_summary=False` to avoid model summary specifications (e.g. number of parameters); set it to `True` if needed."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 17,
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"metadata": {},
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"outputs": [
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n"
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]
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},
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"HPU available: False, using: 0 HPUs\n"
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]
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},
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{
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"data": {
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"application/vnd.jupyter.widget-view+json": {
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"model_id": "775a2d088e304b2589631b176c9e99e2",
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"version_major": 2,
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"version_minor": 0
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},
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"text/plain": [
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"Training: | | 0/? [00:00<?, ?it/s]"
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]
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},
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"metadata": {},
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"output_type": "display_data"
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},
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"`Trainer.fit` stopped: `max_epochs=100` reached.\n",
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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},
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{
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"data": {
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"application/vnd.jupyter.widget-view+json": {
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"model_id": "d858dc0a31214f5f86aae78823525b56",
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"version_major": 2,
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"version_minor": 0
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},
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"text/plain": [
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"Training: | | 0/? [00:00<?, ?it/s]"
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]
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},
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"metadata": {},
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"output_type": "display_data"
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},
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"`Trainer.fit` stopped: `max_epochs=100` reached.\n",
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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},
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{
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"data": {
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"application/vnd.jupyter.widget-view+json": {
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"model_id": "739bf2009f7a48a1b59b7df695276672",
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"version_major": 2,
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"version_minor": 0
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},
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"text/plain": [
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"Training: | | 0/? [00:00<?, ?it/s]"
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]
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},
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"metadata": {},
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"output_type": "display_data"
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},
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"`Trainer.fit` stopped: `max_epochs=100` reached.\n"
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]
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}
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],
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"source": [
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"from lightning.pytorch.loggers import TensorBoardLogger\n",
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"\n",
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"# three run of training, by default it trains for 1000 epochs, we set the max to 100\n",
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"# we reinitialize the model each time otherwise the same parameters will be optimized\n",
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"for _ in range(3):\n",
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" model = FeedForward(\n",
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" layers=[10, 10],\n",
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" func=torch.nn.Tanh,\n",
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" output_dimensions=1,\n",
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" input_dimensions=1,\n",
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" )\n",
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" solver = SupervisedSolver(problem, model, use_lt=False)\n",
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" trainer = Trainer(\n",
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" solver=solver,\n",
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" accelerator=\"cpu\",\n",
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" logger=TensorBoardLogger(save_dir=\"training_log\"),\n",
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" enable_model_summary=False,\n",
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" train_size=1.0,\n",
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" val_size=0.0,\n",
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" test_size=0.0,\n",
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" max_epochs=100,\n",
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" )\n",
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" trainer.train()"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"We can now visualize the logs by simply running `tensorboard --logdir=training_log/` in the terminal. You should obtain a webpage similar to the one shown below if running for 1000 epochs:"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"<p align=\\\"center\\\">\n",
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"<img src=\"../static/logging.png\" alt=\\\"Logging API\\\" width=\\\"400\\\"/>\n",
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"</p>"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"As you can see, by default, **PINA** logs the losses which are shown in the progress bar, as well as the number of epochs. You can always insert more loggings by either defining a **callback** ([more on callbacks](https://lightning.ai/docs/pytorch/stable/extensions/callbacks.html)), or inheriting the solver and modifying the programs with different **hooks** ([more on hooks](https://lightning.ai/docs/pytorch/stable/common/lightning_module.html#hooks)).\n",
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"\n",
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"## Trainer Callbacks\n",
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"\n",
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"Whenever we need to access certain steps of the training for logging, perform static modifications (i.e. not changing the `Solver`), or update `Problem` hyperparameters (static variables), we can use **Callbacks**. Notice that **Callbacks** allow you to add arbitrary self-contained programs to your training. At specific points during the flow of execution (hooks), the Callback interface allows you to design programs that encapsulate a full set of functionality. It de-couples functionality that does not need to be in **PINA** `Solver`s.\n",
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"\n",
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"Lightning has a callback system to execute them when needed. **Callbacks** should capture NON-ESSENTIAL logic that is NOT required for your lightning module to run.\n",
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"\n",
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"The following are best practices when using/designing callbacks:\n",
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"\n",
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"* Callbacks should be isolated in their functionality.\n",
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"* Your callback should not rely on the behavior of other callbacks in order to work properly.\n",
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"* Do not manually call methods from the callback.\n",
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"* Directly calling methods (e.g., on_validation_end) is strongly discouraged.\n",
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"* Whenever possible, your callbacks should not depend on the order in which they are executed.\n",
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"\n",
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"We will try now to implement a naive version of `MetricTraker` to show how callbacks work. Notice that this is a very easy application of callbacks, fortunately in **PINA** we already provide more advanced callbacks in `pina.callbacks`."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 18,
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"metadata": {},
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"outputs": [],
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"source": [
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"from lightning.pytorch.callbacks import Callback\n",
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"from lightning.pytorch.callbacks import EarlyStopping\n",
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"import torch\n",
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"\n",
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"\n",
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"# define a simple callback\n",
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"class NaiveMetricTracker(Callback):\n",
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" def __init__(self):\n",
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" self.saved_metrics = []\n",
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"\n",
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" def on_train_epoch_end(\n",
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" self, trainer, __\n",
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" ): # function called at the end of each epoch\n",
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" self.saved_metrics.append(\n",
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" {key: value for key, value in trainer.logged_metrics.items()}\n",
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" )"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"Let's see the results when applied to the problem. You can define **callbacks** when initializing the `Trainer` by using the `callbacks` argument, which expects a list of callbacks.\n"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 19,
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"metadata": {},
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"outputs": [
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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},
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{
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"data": {
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"application/vnd.jupyter.widget-view+json": {
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"model_id": "f38442d749ad4702a0c99715ecf08c59",
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"version_major": 2,
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"version_minor": 0
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},
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"text/plain": [
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"Training: | | 0/? [00:00<?, ?it/s]"
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]
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},
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"metadata": {},
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"output_type": "display_data"
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},
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{
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"name": "stderr",
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"output_type": "stream",
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"text": [
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"`Trainer.fit` stopped: `max_epochs=10` reached.\n"
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]
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}
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],
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"source": [
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"model = FeedForward(\n",
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" layers=[10, 10],\n",
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" func=torch.nn.Tanh,\n",
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" output_dimensions=1,\n",
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" input_dimensions=1,\n",
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")\n",
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"solver = SupervisedSolver(problem, model, use_lt=False)\n",
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"trainer = Trainer(\n",
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" solver=solver,\n",
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" accelerator=\"cpu\",\n",
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" logger=True,\n",
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" callbacks=[NaiveMetricTracker()], # adding a callbacks\n",
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" enable_model_summary=False,\n",
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" train_size=1.0,\n",
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" val_size=0.0,\n",
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" test_size=0.0,\n",
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" max_epochs=10, # training only for 10 epochs\n",
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")\n",
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"trainer.train()"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"We can easily access the data by calling `trainer.callbacks[0].saved_metrics` (notice the zero representing the first callback in the list given at initialization)."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 20,
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"metadata": {},
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"outputs": [
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{
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"data": {
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"text/plain": [
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"[{'data_loss': tensor(126.2887), 'train_loss': tensor(126.2887)},\n",
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" {'data_loss': tensor(126.2346), 'train_loss': tensor(126.2346)},\n",
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" {'data_loss': tensor(126.1805), 'train_loss': tensor(126.1805)}]"
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]
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},
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"execution_count": 20,
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"metadata": {},
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"output_type": "execute_result"
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}
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],
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"source": [
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"trainer.callbacks[0].saved_metrics[:3] # only the first three epochs"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"PyTorch Lightning also has some built-in `Callbacks` which can be used in **PINA**, [here is an extensive list](https://lightning.ai/docs/pytorch/stable/extensions/callbacks.html#built-in-callbacks). \n",
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"\n",
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"We can, for example, try the `EarlyStopping` routine, which automatically stops the training when a specific metric converges (here the `train_loss`). In order to let the training keep going forever, set `max_epochs=-1`."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 22,
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"metadata": {},
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"outputs": [
|
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{
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"name": "stderr",
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|
"output_type": "stream",
|
|
"text": [
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"GPU available: True (mps), used: False\n",
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"TPU available: False, using: 0 TPU cores\n",
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"HPU available: False, using: 0 HPUs\n"
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]
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}
|
|
],
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"source": [
|
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"model = FeedForward(\n",
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" layers=[10, 10],\n",
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" func=torch.nn.Tanh,\n",
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" output_dimensions=1,\n",
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" input_dimensions=1,\n",
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")\n",
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"solver = SupervisedSolver(problem, model, use_lt=False)\n",
|
|
"trainer = Trainer(\n",
|
|
" solver=solver,\n",
|
|
" accelerator=\"cpu\",\n",
|
|
" max_epochs=-1,\n",
|
|
" enable_model_summary=False,\n",
|
|
" enable_progress_bar=False,\n",
|
|
" val_size=0.2,\n",
|
|
" train_size=0.8,\n",
|
|
" test_size=0.0,\n",
|
|
" callbacks=[EarlyStopping(\"val_loss\")],\n",
|
|
") # adding a callbacks\n",
|
|
"trainer.train()"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "markdown",
|
|
"metadata": {},
|
|
"source": [
|
|
"As we can see the model automatically stop when the logging metric stopped improving!"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "markdown",
|
|
"metadata": {},
|
|
"source": [
|
|
"## Trainer Tips to Boost Accuracy, Save Memory and Speed Up Training\n",
|
|
"\n",
|
|
"Until now we have seen how to choose the right `accelerator`, how to log and visualize the results, and how to interface with the program in order to add specific parts of code at specific points via `callbacks`.\n",
|
|
"Now, we will focus on how to boost your training by saving memory and speeding it up, while maintaining the same or even better degree of accuracy!\n",
|
|
"\n",
|
|
"There are several built-in methods developed in PyTorch Lightning which can be applied straightforward in **PINA**. Here we report some:\n",
|
|
"\n",
|
|
"* [Stochastic Weight Averaging](https://pytorch.org/blog/pytorch-1.6-now-includes-stochastic-weight-averaging/) to boost accuracy\n",
|
|
"* [Gradient Clipping](https://deepgram.com/ai-glossary/gradient-clipping) to reduce computational time (and improve accuracy)\n",
|
|
"* [Gradient Accumulation](https://lightning.ai/docs/pytorch/stable/common/optimization.html#id3) to save memory consumption\n",
|
|
"* [Mixed Precision Training](https://lightning.ai/docs/pytorch/stable/common/optimization.html#id3) to save memory consumption\n",
|
|
"\n",
|
|
"We will just demonstrate how to use the first two and see the results compared to standard training.\n",
|
|
"We use the [`Timer`](https://lightning.ai/docs/pytorch/stable/api/lightning.pytorch.callbacks.Timer.html#lightning.pytorch.callbacks.Timer) callback from `pytorch_lightning.callbacks` to track the times. Let's start by training a simple model without any optimization (train for 500 epochs)."
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "code",
|
|
"execution_count": 23,
|
|
"metadata": {},
|
|
"outputs": [
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Seed set to 42\n",
|
|
"GPU available: True (mps), used: False\n",
|
|
"TPU available: False, using: 0 TPU cores\n",
|
|
"HPU available: False, using: 0 HPUs\n"
|
|
]
|
|
},
|
|
{
|
|
"data": {
|
|
"application/vnd.jupyter.widget-view+json": {
|
|
"model_id": "822b8c60e73f49a486d3d702d413d6ff",
|
|
"version_major": 2,
|
|
"version_minor": 0
|
|
},
|
|
"text/plain": [
|
|
"Training: | | 0/? [00:00<?, ?it/s]"
|
|
]
|
|
},
|
|
"metadata": {},
|
|
"output_type": "display_data"
|
|
},
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"`Trainer.fit` stopped: `max_epochs=500` reached.\n"
|
|
]
|
|
},
|
|
{
|
|
"name": "stdout",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Total training time 15.49781 s\n"
|
|
]
|
|
}
|
|
],
|
|
"source": [
|
|
"from lightning.pytorch.callbacks import Timer\n",
|
|
"from lightning.pytorch import seed_everything\n",
|
|
"\n",
|
|
"# setting the seed for reproducibility\n",
|
|
"seed_everything(42, workers=True)\n",
|
|
"\n",
|
|
"model = FeedForward(\n",
|
|
" layers=[10, 10],\n",
|
|
" func=torch.nn.Tanh,\n",
|
|
" output_dimensions=1,\n",
|
|
" input_dimensions=1,\n",
|
|
")\n",
|
|
"\n",
|
|
"solver = SupervisedSolver(problem, model, use_lt=False)\n",
|
|
"trainer = Trainer(\n",
|
|
" solver=solver,\n",
|
|
" accelerator=\"cpu\",\n",
|
|
" deterministic=True, # setting deterministic=True ensure reproducibility when a seed is imposed\n",
|
|
" max_epochs=500,\n",
|
|
" enable_model_summary=False,\n",
|
|
" callbacks=[Timer()],\n",
|
|
") # adding a callbacks\n",
|
|
"trainer.train()\n",
|
|
"print(f'Total training time {trainer.callbacks[0].time_elapsed(\"train\"):.5f} s')"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "markdown",
|
|
"metadata": {},
|
|
"source": [
|
|
"Now we do the same but with `StochasticWeightAveraging` enabled"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "code",
|
|
"execution_count": 24,
|
|
"metadata": {},
|
|
"outputs": [
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Seed set to 42\n",
|
|
"GPU available: True (mps), used: False\n",
|
|
"TPU available: False, using: 0 TPU cores\n",
|
|
"HPU available: False, using: 0 HPUs\n"
|
|
]
|
|
},
|
|
{
|
|
"data": {
|
|
"application/vnd.jupyter.widget-view+json": {
|
|
"model_id": "dc5f3b47abff4facae7a60d0871f3bfe",
|
|
"version_major": 2,
|
|
"version_minor": 0
|
|
},
|
|
"text/plain": [
|
|
"Training: | | 0/? [00:00<?, ?it/s]"
|
|
]
|
|
},
|
|
"metadata": {},
|
|
"output_type": "display_data"
|
|
},
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Swapping scheduler `ConstantLR` for `SWALR`\n",
|
|
"`Trainer.fit` stopped: `max_epochs=500` reached.\n"
|
|
]
|
|
},
|
|
{
|
|
"name": "stdout",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Total training time 15.52474 s\n"
|
|
]
|
|
}
|
|
],
|
|
"source": [
|
|
"from lightning.pytorch.callbacks import StochasticWeightAveraging\n",
|
|
"\n",
|
|
"# setting the seed for reproducibility\n",
|
|
"seed_everything(42, workers=True)\n",
|
|
"\n",
|
|
"model = FeedForward(\n",
|
|
" layers=[10, 10],\n",
|
|
" func=torch.nn.Tanh,\n",
|
|
" output_dimensions=1,\n",
|
|
" input_dimensions=1,\n",
|
|
")\n",
|
|
"solver = SupervisedSolver(problem, model, use_lt=False)\n",
|
|
"trainer = Trainer(\n",
|
|
" solver=solver,\n",
|
|
" accelerator=\"cpu\",\n",
|
|
" deterministic=True,\n",
|
|
" max_epochs=500,\n",
|
|
" enable_model_summary=False,\n",
|
|
" callbacks=[Timer(), StochasticWeightAveraging(swa_lrs=0.005)],\n",
|
|
") # adding StochasticWeightAveraging callbacks\n",
|
|
"trainer.train()\n",
|
|
"print(f'Total training time {trainer.callbacks[0].time_elapsed(\"train\"):.5f} s')"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "markdown",
|
|
"metadata": {},
|
|
"source": [
|
|
"As you can see, the training time does not change at all! Notice that around epoch 350\n",
|
|
"the scheduler is switched from the defalut one `ConstantLR` to the Stochastic Weight Average Learning Rate (`SWALR`).\n",
|
|
"This is because by default `StochasticWeightAveraging` will be activated after `int(swa_epoch_start * max_epochs)` with `swa_epoch_start=0.7` by default. Finally, the final `train_loss` is lower when `StochasticWeightAveraging` is used.\n",
|
|
"\n",
|
|
"We will now do the same but clippling the gradient to be relatively small."
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "code",
|
|
"execution_count": 25,
|
|
"metadata": {},
|
|
"outputs": [
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Seed set to 42\n",
|
|
"GPU available: True (mps), used: False\n",
|
|
"TPU available: False, using: 0 TPU cores\n",
|
|
"HPU available: False, using: 0 HPUs\n"
|
|
]
|
|
},
|
|
{
|
|
"data": {
|
|
"application/vnd.jupyter.widget-view+json": {
|
|
"model_id": "d475613ad7f34fe6abd182eed8907004",
|
|
"version_major": 2,
|
|
"version_minor": 0
|
|
},
|
|
"text/plain": [
|
|
"Training: | | 0/? [00:00<?, ?it/s]"
|
|
]
|
|
},
|
|
"metadata": {},
|
|
"output_type": "display_data"
|
|
},
|
|
{
|
|
"name": "stderr",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Swapping scheduler `ConstantLR` for `SWALR`\n",
|
|
"`Trainer.fit` stopped: `max_epochs=500` reached.\n"
|
|
]
|
|
},
|
|
{
|
|
"name": "stdout",
|
|
"output_type": "stream",
|
|
"text": [
|
|
"Total training time 15.94719 s\n"
|
|
]
|
|
}
|
|
],
|
|
"source": [
|
|
"# setting the seed for reproducibility\n",
|
|
"seed_everything(42, workers=True)\n",
|
|
"\n",
|
|
"model = FeedForward(\n",
|
|
" layers=[10, 10],\n",
|
|
" func=torch.nn.Tanh,\n",
|
|
" output_dimensions=1,\n",
|
|
" input_dimensions=1,\n",
|
|
")\n",
|
|
"solver = SupervisedSolver(problem, model, use_lt=False)\n",
|
|
"trainer = Trainer(\n",
|
|
" solver=solver,\n",
|
|
" accelerator=\"cpu\",\n",
|
|
" max_epochs=500,\n",
|
|
" enable_model_summary=False,\n",
|
|
" gradient_clip_val=0.1, # clipping the gradient\n",
|
|
" callbacks=[Timer(), StochasticWeightAveraging(swa_lrs=0.005)],\n",
|
|
")\n",
|
|
"trainer.train()\n",
|
|
"print(f'Total training time {trainer.callbacks[0].time_elapsed(\"train\"):.5f} s')"
|
|
]
|
|
},
|
|
{
|
|
"cell_type": "markdown",
|
|
"metadata": {},
|
|
"source": [
|
|
"As we can see, by applying gradient clipping, we were able to achieve even lower error!\n",
|
|
"\n",
|
|
"## What's Next?\n",
|
|
"\n",
|
|
"Now you know how to use the `Trainer` class efficiently in **PINA**! There are several directions you can explore next:\n",
|
|
"\n",
|
|
"1. **Explore Training on Different Devices**: Test training times on various devices (e.g., `TPU`) to compare performance.\n",
|
|
"\n",
|
|
"2. **Reduce Memory Costs**: Experiment with mixed precision training and gradient accumulation to optimize memory usage, especially when training Neural Operators.\n",
|
|
"\n",
|
|
"3. **Benchmark `Trainer` Speed**: Benchmark the training speed of the `Trainer` class for different precisions to identify potential optimizations.\n",
|
|
"\n",
|
|
"4. **...and many more!**: Consider expanding to **multi-GPU** setups or other advanced configurations for large-scale training.\n",
|
|
"\n",
|
|
"For more resources and tutorials, check out the [PINA Documentation](https://mathlab.github.io/PINA/).\n"
|
|
]
|
|
}
|
|
],
|
|
"metadata": {
|
|
"kernelspec": {
|
|
"display_name": "pina",
|
|
"language": "python",
|
|
"name": "python3"
|
|
},
|
|
"language_info": {
|
|
"codemirror_mode": {
|
|
"name": "ipython",
|
|
"version": 3
|
|
},
|
|
"file_extension": ".py",
|
|
"mimetype": "text/x-python",
|
|
"name": "python",
|
|
"nbconvert_exporter": "python",
|
|
"pygments_lexer": "ipython3",
|
|
"version": "3.9.21"
|
|
}
|
|
},
|
|
"nbformat": 4,
|
|
"nbformat_minor": 2
|
|
}
|