NIR <> lava-dl support

pyproject.toml

@@ -59,6 +59,7 @@ pillow = "^9.2.0"
 pytest = "^7.2.0"
 unittest2 = "^1.1.0"
 torch = "^1.13.1"
+nir = "^0.1.0"
 
 [tool.poetry.dev-dependencies]
 bandit = "1.7.4"
@@ -176,4 +177,3 @@ pylint = ["-*"]                             # Disable temporarily until lint fix
 pycodestyle = ["-F401"]                     # Disable a check
 flake8-bandit = ["-S101"]                   # Ignore asserts for tests
 pyflakes = ["-*"]                           # Disable a plugin
-

src/lava/lib/dl/netx/README.md

@@ -54,3 +54,25 @@ conv   : {shape, type, neuron, inChannels, outChannels, kernelSize, stride,
                         |-> this is the description of the compartment parameters
                         |-> {iDecay, vDecay, vThMant, refDelay, ... (other additional params)}
 ```
+
+## Connection to other frameworks via NIR
+
+The neuromorphic intermediate representation (NIR) is a standard for representing neural networks that is supported by various neuromorphic simulators and hardware platforms. You can learn more about the NIR project and the supported frameworks [here](https://github.com/neuromorphs/NIR).
+
+Converting your lava-dl stored using netx to NIR is simple:
+```python
+from lava.lib.dl.netx import nir_lava
+# convert the lava-dl netx model to nir and save to file
+nir_lava.convert_to_nir(net_config='network.net', path='network.nir')
+```
+
+Importing a NIR network into lava-dl works similarly:
+```python
+import nir
+from lava.lib.dl.netx import nir_lava, hdf5
+# import the NIR model
+nir_graph = nir.read('network.nir')
+net = nir_lava.nir_to_lavadl_net(nir_graph)
+```
+
+This enables you to train your network using other frameworks (e.g. snnTorch, Norse, and others - see the NIR project website) and easily import them into lava through lava-dl's netx. 

src/lava/lib/dl/netx/__init__.py

@@ -4,5 +4,6 @@
 from . import hdf5
 from . import blocks
 from . import utils
+from . import nir_lava
 
-__all__ = ['hdf5', 'blocks', 'utils']
+__all__ = ['hdf5', 'blocks', 'utils', 'nir_lava']