tf

The goal of tf is to wrap the TensorFlow C API. It is proof-of-concept only at this point but is able to load and run a SavedModel exported from keras.

Installation

You can install the development version from GitHub with:

# install.packages("remotes")
remotes::install_github("paleolimbot/tf")

You will also need to have the TensorFlow C API installed. You can install this on MacOS with Homebrew (brew install tensorflow). On Linux you will need to download the API, decompress to /usr/local, and configure the linker:

curl https://storage.googleapis.com/tensorflow/libtensorflow/libtensorflow-cpu-linux-x86_64-2.4.0.tar.gz \
  -o tensorflow.tar.gz
sudo tar -C /usr/local -xzf tensorflow.tar.gz
sudo ldconfig

Getting this to work on Windows is a battle for another day but a binary of the library does exist.

Example

This is a basic example which shows you how to solve a common problem:

library(tf)

# load a saved model!
saved <- system.file("extdata/fashion_mnist.zip", package = "tf")
session <- tf_load_session_from_saved_model(saved, "serve")

# run a prediction!
input <- as_tf_tensor(
  tf_fashion_mnist_test_images[1:2, , , drop = FALSE],
  .tf_ptype = "FLOAT"
)

result <- tf_session_run(
  session,
  "serving_default_flatten_input",
  "StatefulPartitionedCall",
  list(input)
)

as.array(result[[1]])
#>              [,1]         [,2]         [,3]         [,4]         [,5]
#> [1,] 2.718334e-07 1.742129e-07 1.181251e-08 1.540148e-08 7.448043e-08
#> [2,] 5.298625e-05 1.177102e-10 9.914962e-01 6.047198e-09 6.181652e-03
#>              [,6]         [,7]         [,8]         [,9]        [,10]
#> [1,] 1.142487e-02 3.363150e-06 2.745604e-02 1.336721e-05 9.611018e-01
#> [2,] 1.532041e-10 2.269099e-03 2.502629e-12 9.825486e-08 2.062938e-12