Computes the n-th forward difference along the given dimension.

The first-order differences are given by out[i] = input[i + 1] - input[i]. Higher-order differences are calculated by using torch_diff() recursively.

Usage

torch_diff(self, n = 1L, dim = -1L, prepend = list(), append = list())

Arguments

self

the tensor to compute the differences on

n

the number of times to recursively compute the difference

dim

the dimension to compute the difference along. Default is the last dimension.

prepend

values to prepend to input along dim before computing the difference. Their dimensions must be equivalent to that of input, and their shapes must match input’s shape except on dim.

append

values to append to input along dim before computing the difference. Their dimensions must be equivalent to that of input, and their shapes must match input’s shape except on dim.

Note

Only n = 1 is currently supported

Examples

if (torch_is_installed()) {
a <- torch_tensor(c(1,2,3))
torch_diff(a)

b <- torch_tensor(c(4, 5))
torch_diff(a, append = b)

c <- torch_tensor(rbind(c(1,2,3), c(3,4,5)))
torch_diff(c, dim = 1)
torch_diff(c, dim = 2) 

}
#> torch_tensor
#>  1  1
#>  1  1
#> [ CPUFloatType{2,2} ]