Chain_matmul

Usage

torch_chain_matmul(matrices)

Arguments

matrices: (Tensors...) a sequence of 2 or more 2-D tensors whose product is to be determined.

TEST

Returns the matrix product of the \(N\) 2-D tensors. This product is efficiently computed using the matrix chain order algorithm which selects the order in which incurs the lowest cost in terms of arithmetic operations ([CLRS]_). Note that since this is a function to compute the product, \(N\) needs to be greater than or equal to 2; if equal to 2 then a trivial matrix-matrix product is returned. If \(N\) is 1, then this is a no-op - the original matrix is returned as is.

Examples

if (torch_is_installed()) {

a = torch_randn(c(3, 4))
b = torch_randn(c(4, 5))
c = torch_randn(c(5, 6))
d = torch_randn(c(6, 7))
torch_chain_matmul(list(a, b, c, d))
}
#> torch_tensor
#>  -5.9863   0.1716   0.0032  -6.9884  -5.7175   4.8060   5.8719
#>  -9.5635   1.3608  -4.3520 -14.4234 -10.6729   8.3121  10.5100
#> -11.2475  -8.0416  19.7909   1.6510  -5.6424   4.9460   3.3274
#> [ CPUFloatType{3,7} ]