Skip to content

Scaling for partly initialized unit triangular #1351

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 8 additions & 17 deletions src/triangular.jl
Original file line number Diff line number Diff line change
Expand Up @@ -1323,15 +1323,6 @@ end
# Generic routines #
####################

function _set_diag!(B::UpperOrLowerTriangular, x)
# get a mutable array to modify the diagonal
Bm = parent(B) isa StridedArray ? B : copy!(similar(B), B)
for i in diagind(Bm.data, IndexStyle(Bm.data))
Bm.data[i] = x
end
Bm
end

for (t, unitt) in ((UpperTriangular, UnitUpperTriangular),
(LowerTriangular, UnitLowerTriangular))
tstrided = t{<:Any, <:StridedMaybeAdjOrTransMat}
Expand All @@ -1344,8 +1335,8 @@ for (t, unitt) in ((UpperTriangular, UnitUpperTriangular),
end

function (*)(A::$unitt, x::Number)
B = $t(A.data)*x
_set_diag!(B, oneunit(eltype(A)) * x)
B = copy!(similar($t(A.data)), A)
B * x
end

(*)(x::Number, A::$t) = $t(x*A.data)
Expand All @@ -1356,8 +1347,8 @@ for (t, unitt) in ((UpperTriangular, UnitUpperTriangular),
end

function (*)(x::Number, A::$unitt)
B = x*$t(A.data)
_set_diag!(B, x * oneunit(eltype(A)))
B = copy!(similar($t(A.data)), A)
x * B
end

(/)(A::$t, x::Number) = $t(A.data/x)
Expand All @@ -1368,8 +1359,8 @@ for (t, unitt) in ((UpperTriangular, UnitUpperTriangular),
end

function (/)(A::$unitt, x::Number)
B = $t(A.data)/x
_set_diag!(B, oneunit(eltype(A)) / x)
B = copy!(similar($t(A.data)), A)
B / x
end

(\)(x::Number, A::$t) = $t(x\A.data)
Expand All @@ -1380,8 +1371,8 @@ for (t, unitt) in ((UpperTriangular, UnitUpperTriangular),
end

function (\)(x::Number, A::$unitt)
B = x\$t(A.data)
_set_diag!(B, x \ oneunit(eltype(A)))
B = copy!(similar($t(A.data)), A)
x \ B
end
end
end
Expand Down
14 changes: 14 additions & 0 deletions test/triangular.jl
Original file line number Diff line number Diff line change
Expand Up @@ -944,4 +944,18 @@ end
@test 2*U == 2*M
end

@testset "scaling partly initialized unit triangular" begin
for T in (UnitUpperTriangular, UnitLowerTriangular)
isupper = T == UnitUpperTriangular
M = Matrix{BigFloat}(undef,2,2)
M[1+!isupper, 1+isupper] = 3
U = T(M)
C = Matrix(U)
@test U * 2 == C * 2
@test 2 * U == 2 * C
@test U / 2 == C / 2
@test 2 \ U == 2 \ C
end
end

end # module TestTriangular