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Installs Torch and its dependencies.


install_torch(reinstall = FALSE, ..., .inform_restart = TRUE)



Re-install Torch even if its already installed?


Currently unused.


if TRUE and running in an interactive() session, after installation it will print a message to inform the user that the session must be restarted for torch to work correctly.


This function is mainly controlled by environment variables that can be used to override the defaults:

  • TORCH_HOME: the installation path. By default dependencies are installed within the package directory. Eg what's given by system.file(package="torch").

  • TORCH_URL: A URL, path to a ZIP file or a directory containing a LibTorch version. Files will be installed/copied to the TORCH_HOME directory.

  • LANTERN_URL: Same as TORCH_URL but for the Lantern library.

  • TORCH_INSTALL_DEBUG: Setting it to 1, shows debug log messages during installation.

  • PRECXX11ABI: Setting it to 1 will will trigger the installation of a Pre-cxx11 ABI installation of LibTorch. This can be useful in environments with older versions of GLIBC like CentOS7 and older Debian/Ubuntu versions.

  • LANTERN_BASE_URL: The base URL for lantern files. This allows passing a directory where lantern binaries are located. The filename is then constructed as usual.

  • TORCH_COMMIT_SHA: torch repository commit sha to be used when querying lantern uploads. Set it to 'none' to avoid looking for build for that commit and use the latest build for the branch.

  • CUDA: We try to automatically detect the CUDA version installed in your system, but you might want to manually set it here. You can also disable CUDA installation by setting it to 'cpu'.

  • TORCH_R_VERSION: The R torch version. It's unlikely that you need to change it, but it can be useful if you don't have the R package installed, but want to install the dependencies.

The TORCH_INSTALL environment variable can be set to 0 to prevent auto-installing torch and TORCH_LOAD set to 0 to avoid loading dependencies automatically. These environment variables are meant for advanced use cases and troubleshooting only. When timeout error occurs during library archive download, or length of downloaded files differ from reported length, an increase of the timeout value should help.