package torch
Install
Dune Dependency
Authors
Maintainers
Sources
md5=45ccaed01b4aea5d1f9ae0c89c85f78b
sha512=c3d02319adb88f641c0eaf312c4a15525a28f1ee8ef46be10111aafbefb40b29fc1746733be49f6a2049a5a17ccc203a8c0481a18f70eed05b9cf4a34830a2c2
Description
The ocaml-torch project provides some OCaml bindings for the PyTorch library. This brings to OCaml NumPy-like tensor computations with GPU acceleration and tape-based automatic differentiation.
Published: 14 Dec 2020
README
ocaml-torch
ocaml-torch provides some ocaml bindings for the PyTorch tensor library. This brings to OCaml NumPy-like tensor computations with GPU acceleration and tape-based automatic differentiation.
These bindings use the PyTorch C++ API and are mostly automatically generated. The current GitHub tip and the opam package v0.7 corresponds to PyTorch v1.7.0.
On Linux note that you will need the PyTorch version using the cxx11 abi cpu version, cuda 10.2 version.
Opam Installation
The opam package can be installed using the following command. This automatically installs the CPU version of libtorch.
opam install torch
You can then compile some sample code, see some instructions below. ocaml-torch can also be used in interactive mode via utop or ocaml-jupyter.
Here is a sample utop session.
Build a Simple Example
To build a first torch program, create a file example.ml
with the following content.
open Torch
let () =
let tensor = Tensor.randn [ 4; 2 ] in
Tensor.print tensor
Then create a dune
file with the following content:
(executables
(names example)
(libraries torch))
Run dune exec example.exe
to compile the program and run it!
Alternatively you can first compile the code via dune build example.exe
then run the executable _build/default/example.exe
(note that building the bytecode target example.bc
may not work on macos).
Tutorials
Examples
Below is an example of a linear model trained on the MNIST dataset (full code).
(* Create two tensors to store model weights. *)
let ws = Tensor.zeros [image_dim; label_count] ~requires_grad:true in
let bs = Tensor.zeros [label_count] ~requires_grad:true in
let model xs = Tensor.(mm xs ws + bs) in
for index = 1 to 100 do
(* Compute the cross-entropy loss. *)
let loss =
Tensor.cross_entropy_for_logits (model train_images) ~targets:train_labels
in
Tensor.backward loss;
(* Apply gradient descent, disable gradient tracking for these. *)
Tensor.(no_grad (fun () ->
ws -= grad ws * f learning_rate;
bs -= grad bs * f learning_rate));
(* Compute the validation error. *)
let test_accuracy =
Tensor.(argmax (model test_images) = test_labels)
|> Tensor.to_kind ~kind:(T Float)
|> Tensor.sum
|> Tensor.float_value
|> fun sum -> sum /. test_samples
in
printf "%d %f %.2f%%\n%!" index (Tensor.float_value loss) (100. *. test_accuracy);
done
A simplified version of char-rnn illustrating character level language modeling using Recurrent Neural Networks.
Neural Style Transfer applies the style of an image to the content of another image. This uses some deep Convolutional Neural Network.
Models and Weights
Various pre-trained computer vision models are implemented in the vision library. The weight files can be downloaded at the following links:
ResNet-18 weights.
ResNet-34 weights.
ResNet-50 weights.
ResNet-101 weights.
ResNet-152 weights.
DenseNet-121 weights.
DenseNet-161 weights.
DenseNet-169 weights.
SqueezeNet 1.0 weights.
SqueezeNet 1.1 weights.
VGG-13 weights.
VGG-16 weights.
AlexNet weights.
Inception-v3 weights.
MobileNet-v2 weights.
EfficientNet b0 weights, b1 weights, b2 weights, b3 weights, b4 weights.
Running the pre-trained models on some sample images can the easily be done via the following commands.
dune exec examples/pretrained/predict.exe path/to/resnet18.ot tiger.jpg
Natural Language Processing models based on BERT can be found in the ocaml-torch repo.
Alternative Installation Option
This alternative way to install ocaml-torch could be useful to run with GPU acceleration enabled.
The libtorch library can be downloaded from the PyTorch website (1.7.0 cpu version).
Download and extract the libtorch library then to build all the examples run:
export LIBTORCH=/path/to/libtorch
git clone https://github.com/LaurentMazare/ocaml-torch.git
cd ocaml-torch
make all
Dependencies (15)
- stdio
- sexplib
- ppx_sexp_conv
- ppx_expect
- ppx_custom_printf
- ocaml-compiler-libs
-
ocaml
>= "4.08"
- npy
-
libtorch
>= "1.7.0" & < "1.8.0"
- dune-configurator
-
dune
>= "1.3.0"
- ctypes-foreign
-
ctypes
>= "0.11"
- cmdliner
-
base
>= "v0.11.0" & < "v0.17"
Dev Dependencies
None
Used by
None
Conflicts
None