Metadata-Version: 2.1
Name: easy-module-attribute-getter
Version: 0.9.16
Summary: Select module classes and functions using yaml, without any if-statements.
Home-page: https://github.com/KevinMusgrave/easy_module_attribute_getter
Author: Kevin Musgrave
Author-email: tkm45@cornell.edu
License: UNKNOWN
Platform: UNKNOWN
Classifier: Programming Language :: Python :: 3
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Requires-Python: >=3.7
Description-Content-Type: text/markdown
Requires-Dist: PyYAML

# easy_module_attribute_getter

## Installation
```
pip install easy_module_attribute_getter
```

## The Problem: unmaintainable if-statements and switches
It's common to specify script parameters in yaml config files. For example:
```
models:
  modelA:
    densenet121:
      pretrained: True
      memory_efficient: True
  modelB:
    resnext50_32x4d:
      pretrained: True

losses:
  lossA:
    CrossEntropyLoss:
  lossB:
    L1Loss:
```
Usually, the config file is loaded and then various if-statements or switches are used to instantiate objects etc:
```
if args.models["modelA"] == "densenet121":
  modelA = torchvision.models.densenet121(pretrained = args.pretrained)
elif args.models["modelA"] == "googlenet":
  modelA = torchvision.models.googlenet(pretrained = args.pretrained)
elif args.models["modelA"] == "resnet50":
  modelA = torchvision.models.resnet50(pretrained = args.pretrained)
elif args.models["modelA"] == "inception_v3":
  modelA = torchvision.models.inception_v3(pretrained = args.pretrained)
...
if args.losses["lossA"] == "CrossEntropyLoss":
  lossA = torch.nn.CrossEntropyLoss()
elif args.losses["lossA"] == "L1Loss":
  lossA = torch.nn.L1Loss()
...
```
## The Solution
### Use this package, and get rid of all those annoying if-statements and switches:
```
from easy_module_attribute_getter import PytorchGetter
pytorch_getter = PytorchGetter()
models = pytorch_getter.get_multiple("model", args.models)
losses = pytorch_getter.get_multiple("loss", args.losses)
```
"models" and "losses" are dictionaries that map from strings to the desired objects.

### Load one or multiple yaml files into one args object
```
from easy_module_attribute_getter import YamlReader
yaml_reader = YamlReader()
args, _, _ = yaml_reader.load_yamls(['example.yaml'])
```
Provide a list of filepaths:
```
args, _, _ = yaml_reader.load_yamls(['models.yaml', 'optimizers.yaml', 'transforms.yaml'])
```
Or provide a root path and a dictionary mapping subfolder names to the bare filename
```
root_path = "/where/your/yaml/subfolders/are/"
subfolder_to_name_dict = {"models": "default", "optimizers": "special_trial", "transforms": "blah"}
args, _, _ = yaml_reader.load_yamls(root_path=root_path, subfolder_to_name_dict=subfolder_to_name_dict)
```

### Override complex config options via the command line:
The example yaml file contains 'models' which maps to a nested dictionary. This key can optionally be overridden at the command line, using the standard python notation for nested dictionaries. In this example, instead of loading densenet121 and resnext50, as specified in the config file, the program will instead load googlenet and resnet18.
```
python example.py --models {modelA: {googlenet: {pretrained: True}}, modelB: {resnet18: {pretrained: True}}}
```

### Easily register your own modules into an existing getter.
```
from pytorch_metric_learning import losses, miners, samplers 
pytorch_getter = PytorchGetter()
pytorch_getter.register('loss', losses) 
pytorch_getter.register('miner', miners)
pytorch_getter.register('sampler', samplers)
metric_loss = pytorch_getter.get('loss', class_name='ProxyNCALoss', return_uninitialized=True)
kl_div_loss = pytorch_getter.get('loss', class_name='KLDivLoss', return_uninitialized=True)
```
In the above example, the 'loss' key already exists, so the 'losses' module will be appended to the existing module.


## Pytorch-specific features
### Transforms
Specify transforms in your config file:
```
transforms:
  train:
    Resize:
      size: 256
    RandomResizedCrop:
      scale: 0.16 1
      ratio: 0.75 1.33
      size: 227
    RandomHorizontalFlip:
      p: 0.5

  eval:
    Resize:
      size: 256
    CenterCrop:
      size: 227
```
Then load composed transforms in your script:
```
transforms = {}
for k, v in args.transforms.items():
    transforms[k] = pytorch_getter.get_composed_img_transform(v, mean = [0.485, 0.456, 0.406], std = [0.229, 0.224, 0.225])
```
The transforms dict now contains:
```
{'train': Compose(
    Resize(size=256, interpolation=PIL.Image.BILINEAR)
    RandomResizedCrop(size=(227, 227), scale=(0.16, 1), ratio=(0.75, 1.33), interpolation=PIL.Image.BILINEAR)
    RandomHorizontalFlip(p=0.5)
    ToTensor()
    Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
), 'eval': Compose(
    Resize(size=256, interpolation=PIL.Image.BILINEAR)
    CenterCrop(size=(227, 227))
    ToTensor()
    Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
)}
```


### Optimizers, schedulers, and gradient clippers
Optionally specify the scheduler and gradient clipping norm, within the optimizer parameters.
```
optimizers:
  modelA:
    Adam:
      lr: 0.00001
      weight_decay: 0.00005
      scheduler:
        StepLR:
          step_size: 2
          gamma: 0.95
      clip_grad_norm: 1
  modelB:
    RMSprop:
      lr: 0.00001
      weight_decay: 0.00005
```
Create the optimizers:
```
optimizers = {}
schedulers = {}
grad_clippers = {}
for k, v in models.items():
	optimizers[k], schedulers[k], grad_clippers[k] = pytorch_getter.get_optimizer(v, yaml_dict=args.optimizers[k])
```


