mirror of
https://github.com/wassname/pytorch-lightning.git
synced 2026-10-28 13:20:31 +08:00
Jirka Borovec
3a58937d8b
* rename nb -> num * flake8 * batch_nb, epoch_nb, gpu_nb, split_nb * add _num deprecations
61 lines
1.9 KiB
Markdown
61 lines
1.9 KiB
Markdown
## New project Quick Start
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To start a new project define two files, a LightningModule and a Trainer file.
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To illustrate Lightning power and simplicity, here's an example of a typical research flow.
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### Case 1: BERT
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Let's say you're working on something like BERT but want to try different ways of training or even different networks.
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You would define a single LightningModule and use flags to switch between your different ideas.
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```python
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class BERT(pl.LightningModule):
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def __init__(self, model_name, task):
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self.task = task
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if model_name == 'transformer':
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self.net = Transformer()
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elif model_name == 'my_cool_version':
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self.net = MyCoolVersion()
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def training_step(self, batch, batch_idx):
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if self.task == 'standard_bert':
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# do standard bert training with self.net...
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# return loss
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if self.task == 'my_cool_task':
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# do my own version with self.net
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# return loss
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```
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### Case 2: COOLER NOT BERT
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But if you wanted to try something **completely** different, you'd define a new module for that.
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```python
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class CoolerNotBERT(pl.LightningModule):
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def __init__(self):
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self.net = ...
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def training_step(self, batch, batch_idx):
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# do some other cool task
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# return loss
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```
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### Rapid research flow
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Then you could do rapid research by switching between these two and using the same trainer.
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```python
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if use_bert:
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model = BERT()
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else:
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model = CoolerNotBERT()
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trainer = Trainer(gpus=4, use_amp=True)
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trainer.fit(model)
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```
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Notice a few things about this flow:
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1. You're writing pure PyTorch... no unnecessary abstractions or new libraries to learn.
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2. You get free GPU and 16-bit support without writing any of that code in your model.
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3. You also get all of the capabilities below (without coding or testing yourself).
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