# torch

## Installation

torch can be installed from CRAN with:

`install.packages("torch")`

You can also install the development version with:

`remotes::install_github("mlverse/torch")`

At the first package load additional software will be installed. See
also the full installation
guide here.

## Examples

You can create torch tensors from R objects with the
`torch_tensor`

function and convert them back to R objects
with `as_array`

.

```
library(torch)
x <- array(runif(8), dim = c(2, 2, 2))
y <- torch_tensor(x, dtype = torch_float64())
y
#> torch_tensor
#> (1,.,.) =
#> 0.6192 0.5800
#> 0.2488 0.3681
#>
#> (2,.,.) =
#> 0.0042 0.9206
#> 0.4388 0.5664
#> [ CPUDoubleType{2,2,2} ]
identical(x, as_array(y))
#> [1] TRUE
```

### Simple Autograd Example

In the following snippet we let torch, using the autograd feature,
calculate the derivatives:

```
x <- torch_tensor(1, requires_grad = TRUE)
w <- torch_tensor(2, requires_grad = TRUE)
b <- torch_tensor(3, requires_grad = TRUE)
y <- w * x + b
y$backward()
x$grad
#> torch_tensor
#> 2
#> [ CPUFloatType{1} ]
w$grad
#> torch_tensor
#> 1
#> [ CPUFloatType{1} ]
b$grad
#> torch_tensor
#> 1
#> [ CPUFloatType{1} ]
```

## Contributing

No matter your current skills itâ€™s possible to contribute to
`torch`

development. See the contributing
guide for more information.