new finite MPO test

Author: ryanlevy

test/test_modelMPOs.jl

@@ -0,0 +1,88 @@
+using ITensors, ITensorMPS
+using ITensorInfiniteMPS
+using Test
+
+@testset verbose = true "Heisenberg Model Test" begin
+  cell_widths = [2, 3, 4, 5]
+  @testset "cell_width=$width" for width in cell_widths
+    model = Model("heisenberg")
+    os = ITensorInfiniteMPS.opsum_finite(model, width;)
+
+    connections = []
+    for term in os
+      push!(connections, sort(ITensors.sites(term)))
+    end
+    for i in 1:(width - 1)
+      @test [i, i + 1] ∈ connections
+    end
+  end
+end
+
+@testset verbose = true "Heisenberg2D Model Test" begin
+  widths = [2, 3, 4, 5, 6]
+  cell_widths = [2, 3, 4, 5]
+  @testset "cell_width=$cell_width width=$width" for cell_width in cell_widths,
+    width in widths
+
+    model = Model("heisenberg2D")
+
+    os = ITensorInfiniteMPS.opsum_finite(model, cell_width * width; width, yperiodic)
+
+    connections = []
+    for term in os
+      push!(connections, ITensors.sites(term))
+    end
+    for col in 1:(cell_width - 1)
+      for row in 1:(width - 1)
+        i = (col - 1) * width + row
+        @test [i, i + 1] ∈ connections
+        @test [i, i + width] ∈ connections
+      end
+      (yperiodic && width > 2) && @test [i, i + width - 1] ∈ connections
+    end
+    # the above forgets the last horizontal bond
+    for col in 1:(cell_width - 1)
+      i = (col - 1) * width + width
+      @test [i, i + width] ∈ connections
+    end
+  end
+end
+
+@testset verbose = true "Ising Model Test" begin
+  cell_widths = [2, 3, 4, 5]
+  @testset "cell_width=$width" for width in cell_widths
+    model = Model("ising")
+    os = ITensorInfiniteMPS.opsum_finite(model, width;)
+
+    connections = []
+    for term in os
+      push!(connections, sort(ITensors.sites(term)))
+    end
+    for i in 1:(width - 1)
+      @test [i, i + 1] ∈ connections
+      @test [i] ∈ connections
+    end
+  end
+end
+
+@testset verbose = true "Hubbard Model Test" begin
+  t, U = 1.0, 4.0
+  cell_widths = [2, 3, 4, 5]
+  @testset "cell_width=$width" for width in cell_widths
+    model = Model("hubbard")
+    os = ITensorInfiniteMPS.opsum_finite(model, width; t, U)
+
+    connections = []
+    for term in os
+      push!(connections, ITensors.sites(term))
+    end
+    for i in 1:(width - 1)
+      @test [i, i + 1] ∈ connections
+      @test [i + 1, i] ∈ connections
+      @test [i] ∈ connections
+    end
+    @test [width] ∈ connections
+  end
+end
+
+nothing