fix braille and add small test

src/MPSKit.jl

@@ -120,6 +120,7 @@ include("operators/projection.jl")
 include("operators/timedependence.jl")
 include("operators/multipliedoperator.jl")
 include("operators/lazysum.jl")
+include("operators/show.jl")
 
 include("transfermatrix/transfermatrix.jl")
 include("transfermatrix/transfer.jl")

src/operators/abstractmpo.jl

@@ -82,80 +82,6 @@ function remove_orphans!(mpo::SparseMPO; tol=eps(real(scalartype(mpo)))^(3 / 4))
     return mpo
 end
 
-# Show
-# ----
-function Base.show(io::IO, ::MIME"text/plain", W::AbstractMPO)
-    L = length(W)
-    println(io, L == 1 ? "single site " : "$L-site ", typeof(W), ":")
-    context = IOContext(io, :typeinfo => eltype(W), :compact => true)
-    return show(context, W)
-end
-
-Base.show(io::IO, mpo::AbstractMPO) = show(convert(IOContext, io), mpo)
-function Base.show(io::IOContext, mpo::AbstractMPO)
-    charset = (; top="┬", bot="┴", mid="┼", ver="│", dash="──")
-    limit = get(io, :limit, false)::Bool
-    half_screen_rows = limit ? div(displaysize(io)[1] - 8, 2) : typemax(Int)
-    L = length(mpo)
-
-    # used to align all mposite infos regardless of the length of the mpo (100 takes up more space than 5)
-    npad = floor(Int, log10(L))
-    mpoletter = mpo isa MPOHamiltonian ? "W" : "O"
-    isfinite = (mpo isa FiniteMPO) || (mpo isa FiniteMPOHamiltonian)
-
-    !isfinite && println(io, "╷  ⋮")
-    for site in reverse(1:L)
-        if site < half_screen_rows || site > L - half_screen_rows
-            if site == L && isfinite
-                println(io, charset.top, " $mpoletter[$site]: ",
-                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
-            elseif (site == 1) && isfinite
-                println(io, charset.bot, " $mpoletter[$site]: ",
-                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
-            else
-                println(io, charset.mid, " $mpoletter[$site]: ",
-                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
-            end
-        elseif site == half_screen_rows
-            println(io, "   ", "⋮")
-        end
-    end
-    !isfinite && println(io, "╵  ⋮")
-    return nothing
-end
-
-function braille(H::SparseMPO)
-    isfinite = (H isa FiniteMPO) || (H isa FiniteMPOHamiltonian)
-    dash = "🭻"
-    stride = 2 #amount of dashes between braille
-    L = length(H)
-
-    brailles = Vector{Vector{String}}(undef, L)
-    buffer = IOBuffer()
-    for (i, W) in enumerate(H)
-        BlockTensorKit.show_braille(buffer, W)
-        brailles[i] = split(String(take!(buffer)))
-    end
-
-    maxheight = maximum(length.(brailles))
-
-    for i in 1:maxheight
-        line = ""
-        line *= ((i == 1 && !isfinite) ? ("... " * dash) : " ")
-        line *= (i > 1 && !isfinite) ? "    " : ""
-        for (j, braille) in enumerate(brailles)
-            line *= (checkbounds(Bool, braille, i) ? braille[i] :
-                     repeat(" ", length(braille[1])))
-            if j < L
-                line *= repeat(((i == 1) ? dash : " "), stride)
-            end
-        end
-        line *= ((i == 1 && !isfinite) ? (dash * " ...") : " ")
-        println(line)
-    end
-    return nothing
-end
-
 # Linear Algebra
 # --------------
 Base.:+(mpo::AbstractMPO) = scale(mpo, One())

src/operators/show.jl

@@ -0,0 +1,90 @@
+# AbstractMPO
+# -----------
+function Base.show(io::IO, ::MIME"text/plain", W::AbstractMPO)
+    L = length(W)
+    println(io, L == 1 ? "single site " : "$L-site ", typeof(W), ":")
+    context = IOContext(io, :typeinfo => eltype(W), :compact => true)
+    return show(context, W)
+end
+
+Base.show(io::IO, mpo::AbstractMPO) = show(convert(IOContext, io), mpo)
+function Base.show(io::IOContext, mpo::AbstractMPO)
+    charset = (; top="┬", bot="┴", mid="┼", ver="│", dash="──")
+    limit = get(io, :limit, false)::Bool
+    half_screen_rows = limit ? div(displaysize(io)[1] - 8, 2) : typemax(Int)
+    L = length(mpo)
+
+    # used to align all mposite infos regardless of the length of the mpo (100 takes up more space than 5)
+    npad = floor(Int, log10(L))
+    mpoletter = mpo isa MPOHamiltonian ? "W" : "O"
+    isfinite = (mpo isa FiniteMPO) || (mpo isa FiniteMPOHamiltonian)
+
+    !isfinite && println(io, "╷  ⋮")
+    for site in reverse(1:L)
+        if site < half_screen_rows || site > L - half_screen_rows
+            if site == L && isfinite
+                println(io, charset.top, " $mpoletter[$site]: ",
+                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
+            elseif (site == 1) && isfinite
+                println(io, charset.bot, " $mpoletter[$site]: ",
+                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
+            else
+                println(io, charset.mid, " $mpoletter[$site]: ",
+                        repeat(" ", npad - floor(Int, log10(site))), mpo[site])
+            end
+        elseif site == half_screen_rows
+            println(io, "   ", "⋮")
+        end
+    end
+    !isfinite && println(io, "╵  ⋮")
+    return nothing
+end
+
+# braille
+# -------
+"""
+    braille(io::IO, H::Union{SparseMPO, MPOHamiltonian})
+    braille(H::Union{SparseMPO, MPOHamiltonian})
+
+Prints a compact, human-readable "braille" visualization of a sparseMPO or MPOHamiltonian.
+Each site of the MPO is represented as a block of Unicode braille characters, with sites separated by dashes.
+This visualization is useful for quickly inspecting the structure and sparsity pattern of MPOs.
+
+# Arguments
+- `io::IO`: The output stream to print to (e.g., `stdout`).
+- `H::Union{SparseMPO, MPOHamiltonian}`: The `SparseMPO` or `MPOHamiltonian` to visualize.
+
+If called without an `io` argument, output is printed to `stdout`.
+"""
+function braille(io::IO, H::Union{SparseMPO,MPOHamiltonian})
+    dash = "🭻"
+    stride = 2 #amount of dashes between braille
+    L = length(H)
+
+    brailles = Vector{Vector{String}}(undef, L)
+    buffer = IOBuffer()
+    for (i, W) in enumerate(H)
+        BlockTensorKit.show_braille(buffer, W)
+        brailles[i] = split(String(take!(buffer)))
+    end
+
+    maxheight = maximum(length.(brailles))
+
+    for i in 1:maxheight
+        line = ""
+        line *= ((i == 1 && !isfinite(H)) ? ("... " * dash) : " ")
+        line *= (i > 1 && !isfinite(H)) ? "    " : ""
+        for (j, braille) in enumerate(brailles)
+            line *= (checkbounds(Bool, braille, i) ? braille[i] :
+                     repeat(" ", length(braille[1])))
+            if j < L
+                line *= repeat(((i == 1) ? dash : " "), stride)
+            end
+        end
+        line *= ((i == 1 && !isfinite(H)) ? (dash * " ...") : " ")
+        println(io, line)
+    end
+    return nothing
+end
+
+braille(H::Union{SparseMPO,MPOHamiltonian}) = braille(stdout, H)

test/other.jl

@@ -63,4 +63,34 @@ end
     end
 end
 
+@testset "braille" begin
+    # Infinite Hamiltonians and MPOs
+    # -------------------------------
+    H = transverse_field_ising()
+    buffer = IOBuffer()
+    braille(buffer, H)
+    output = String(take!(buffer))
+    check = "... 🭻⎡⠉⢀⎤🭻 ...\n     ⎣⠀⢀⎦ \n"
+    @test output == check
+
+    O = make_time_mpo(H, 1.0, TaylorCluster(3, false, false))
+    braille(buffer, O)
+    output = String(take!(buffer))
+    check = "... 🭻⎡⡏⠉⠒⠔⎤🭻 ...\n     ⎣⡇⠀⠀⡂⎦ \n"
+    @test output == check
+
+    # Finite Hamiltonians and MPOs
+    # ----------------------------
+    H = transverse_field_ising(; L=4)
+    braille(buffer, H)
+    output = String(take!(buffer))
+    check = " ⎡⠉⠀⎤🭻🭻⎡⠉⢀⎤🭻🭻⎡⠉⢀⎤🭻🭻⎡⡀⠀⎤ \n ⎣⠀⠀⎦  ⎣⠀⢀⎦  ⎣⠀⢀⎦  ⎣⡀⠀⎦ \n"
+    @test output == check
+
+    O = make_time_mpo(H, 1.0, TaylorCluster(3, false, false))
+    braille(buffer, O)
+    output = String(take!(buffer))
+    check = " ⎡⠉⠉⎤🭻🭻⎡⠍⠉⠤⠠⎤🭻🭻⎡⡏⠉⠒⠔⎤🭻🭻⎡⡇⠀⎤ \n ⎣⠀⠀⎦  ⎣⡂⠀⠀⠂⎦  ⎣⡇⠀⠀⡂⎦  ⎣⡇⠀⎦ \n"
+    @test output == check
+end
 end