Triangular_solve

Usage

torch_triangular_solve(
  self,
  A,
  upper = TRUE,
  transpose = FALSE,
  unitriangular = FALSE
)

Arguments

self: (Tensor) multiple right-hand sides of size \((*, m, k)\) where \(*\) is zero of more batch dimensions (\(b\))
A: (Tensor) the input triangular coefficient matrix of size \((*, m, m)\) where \(*\) is zero or more batch dimensions
upper: (bool, optional) whether to solve the upper-triangular system of equations (default) or the lower-triangular system of equations. Default: TRUE.
transpose: (bool, optional) whether \(A\) should be transposed before being sent into the solver. Default: FALSE.
unitriangular: (bool, optional) whether \(A\) is unit triangular. If TRUE, the diagonal elements of \(A\) are assumed to be 1 and not referenced from \(A\). Default: FALSE.

triangular_solve(input, A, upper=TRUE, transpose=False, unitriangular=False) -> (Tensor, Tensor)

Solves a system of equations with a triangular coefficient matrix \(A\) and multiple right-hand sides \(b\).

In particular, solves \(AX = b\) and assumes \(A\) is upper-triangular with the default keyword arguments.

torch_triangular_solve(b, A) can take in 2D inputs b, A or inputs that are batches of 2D matrices. If the inputs are batches, then returns batched outputs X

Examples

if (torch_is_installed()) {

A = torch_randn(c(2, 2))$triu()
A
b = torch_randn(c(2, 3))
b
torch_triangular_solve(b, A)
}
#> [[1]]
#> torch_tensor
#> -0.4159 -19.8541 -28.8686
#> -9.9554 -26.7462 -40.0722
#> [ CPUFloatType{2,3} ]
#> 
#> [[2]]
#> torch_tensor
#>  0.2344 -0.1714
#>  0.0000 -0.0268
#> [ CPUFloatType{2,2} ]
#>