yapanuwan
/
BergEC-jl
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Kronecker sum implemented

This commit is contained in:
Nuwan Yapa 2024-04-29 10:58:24 -04:00
parent 1f834f72e9
commit 222ab12ef7
1 changed files with 9 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
helper.jl
View File

@ -1,3 +1,5 @@
using LinearAlgebra
"Sum over array while minimizing catastrophic cancellation as much as possible"
function better_sum(arr::Array{Float64})
pos_arr = arr[arr .> 0]
@ -15,4 +17,10 @@ better_sum(arr::Array{ComplexF64}) = better_sum(real.(arr)) + 1im * better_sum(i
triangle_ineq(l1, l2, L) = abs(l1 - l2) ≤ L && L ≤ (l1 + l2)
"Nearest value in a list to a given reference point"
nearest(list::Array, ref) = list[argmin(norm.(list .- ref))]
nearest(list::Array, ref) = list[argmin(norm.(list .- ref))]
"Simple implementation of the Kronecker sum"
function kron_sum(A::AbstractMatrix, B::AbstractMatrix)
@assert size(A, 1) == size(A, 2) && size(B, 1) == size(B, 2) "Matrices should be square"
return kron(A, I(size(B, 1))) + kron(B, I(size(A, 1)))
end