## coinstac-sparse-dinunet
#### Distributed Sparse Neural Network implementation on COINSTAC.


```
pip install coinstac-sparse-dinunet
```
#### Specify supported packages like pytorch & torchvision in a requirements.txt file
#### Highlights:
```
1. Creates sparse network based on single shot pruning SNIP algorithm (https://arxiv.org/abs/1810.02340).
2. Performs distributed training and optimization with reduced bandwidth.
3. Automatic data splitting/k-fold cross validation.
4. Automatic model checkpointing.
5. GPU enabled local sites.
6. Customizable metrics(w/Auto serialization between nodes) to work with any schemes.
7. We can integrate any custom reduction and learning mechanism by extending coinstac_sparse_dinunet.distrib.reducer/learner.
...
```
<hr />
### [Running an analysis](https://github.com/trendscenter/coinstac-instructions/blob/master/coinstac-how-to-run-analysis.md) in the coinstac App.
### Add a new NN computation to COINSTAC (Development guide):
#### imports
```python
from coinstac_sparse_dinunet import COINNDataset, COINNTrainer, COINNLocal
from coinstac_sparse_dinunet.metrics import COINNAverages, Prf1a
```
#### 1. Define Data Loader
```python
class MyDataset(COINNDataset):
def __init__(self, **kw):
super().__init__(**kw)
self.labels = None
def load_index(self, id, file):
data_dir = self.path(id, 'data_dir') # data_dir comes from inputspecs.json
...
self.indices.append([id, file])
def __getitem__(self, ix):
id, file = self.indices[ix]
data_dir = self.path(id, 'data_dir') # data_dir comes from inputspecs.json
label_dir = self.path(id, 'label_dir') # label_dir comes from inputspecs.json
...
# Logic to load, transform single data item.
...
return {'inputs':.., 'labels': ...}
```
#### 2. Define Trainer
```python
class MyTrainer(COINNTrainer):
def __init__(self, **kw):
super().__init__(**kw)
def _init_nn_model(self):
self.nn['model'] = MYModel(in_size=self.cache['input_size'], out_size=self.cache['num_class'])
def single_iteration_for_masking(self, model, batch):
#Defines sparsity level, loss function and other parameters to perform masking using SNIP
sparsity_level = 0.85
inputs, labels = batch['inputs'].to(self.device['gpu']).float(), batch['labels'].to(self.device['gpu']).long()
indices = batch['ix'].to(self.device['gpu']).long()
model.zero_grad()
out = F.log_softmax(model.forward(inputs), 1)
loss = F.nll_loss(out, labels)
return {'out': out, 'loss': loss, 'indices': indices, 'sparsity_level': sparsity_level}
def iteration(self, batch):
inputs, labels = batch['inputs'].to(self.device['gpu']).float(), batch['labels'].to(self.device['gpu']).long()
out = F.log_softmax(self.nn['model'](inputs), 1)
loss = F.nll_loss(out, labels)
_, predicted = torch.max(out, 1)
score = self.new_metrics()
score.add(predicted, labels)
val = self.new_averages()
val.add(loss.item(), len(inputs))
return {'out': out, 'loss': loss, 'averages': val,
'metrics': score, 'prediction': predicted}
```
<hr />
#### Advanced use cases:
* **Define custom metrics:**
- Extend [coinstac_sparse_dinunet.metrics.COINNMetrics](https://github.com/bishalth01/coinstac_sparse_dinunet/blob/master/coinstac_sparse_dinunet/metrics/metrics.py)
- Example: [coinstac_sparse_dinunet.metrics.Prf1a](https://github.com/bishalth01/coinstac_sparse_dinunet/blob/master/coinstac_sparse_dinunet/metrics/metrics.py) for Precision, Recall, F1, and Accuracy
* **Define [Custom Learner](https://github.com/bishalth01/coinstac_sparse_dinunet/blob/master/coinstac_sparse_dinunet/distrib/learner.py) / [custom Aggregator]/ [custom Aggregator](https://github.com/bishalth01/coinstac_sparse_dinunet/blob/master/coinstac_sparse_dinunet/distrib/reducer.py) (Default is Distributed SGD)**
#### Referenced from Trends Center coinstac-dinunet repository (https://github.com/trendscenter/coinstac-dinunet)