Test zero-residual solution

test/test_cg_lanczos.jl

@@ -62,3 +62,13 @@ shifts = [-4, -3, 2;]
 (x, stats) = cg_lanczos_shift_par(full(A), b, [1:6;]);
 show(stats);
 
+# Test b == 0
+(x, stats) = cg_lanczos(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"
+(x, stats) = cg_lanczos_shift_par(A, zeros(size(A,1)), [1:6;])
+@test x == zeros(size(A,1), 6)
+@test stats.status == "x = 0 is a zero-residual solution"
+(x, stats) = cg_lanczos_shift_seq(A, zeros(size(A,1)), [1:6;])
+@test x == zeros(size(A,1), 6)
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_cgls.jl

@@ -37,3 +37,7 @@ resid = norm(A' * M * (A * x - b)) / sqrt(dot(b, M * b));
 (x, stats) = cgls(sparse(full(A)), b);
 show(stats);
 
+# Test b == 0
+(x, stats) = cgls(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_cgne.jl

@@ -78,3 +78,7 @@ A = ones(5, 3); b = rand(5); b[1] = -1.0;
 (x, stats, resid) = test_cgne(sparse(A), b, λ=1.0e-3);
 show(stats);
 
+# Test b == 0
+(x, stats) = cgne(A, zeros(size(A,1)), λ=1.0e-3)
+@test x == zeros(size(A,2))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_craigmr.jl

@@ -90,3 +90,9 @@ A = ones(5, 3); b = rand(5); b[1] = -1.0;
 # Code coverage.
 (x, y, stats) = craigmr(sparse(A), b, λ=1.0e-3);
 show(stats);
+
+# Test b == 0
+(x, y, stats) = craigmr(A, zeros(size(A,1)), λ=1.0e-3)
+@test x == zeros(size(A,2))
+@test y == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_crls.jl

@@ -37,3 +37,7 @@ resid = norm(A' * M * (A * x - b)) / sqrt(dot(b, M * b));
 (x, stats) = crls(sparse(full(A)), b);
 show(stats);
 
+# Test b == 0
+(x, stats) = crls(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_crmr.jl

@@ -81,3 +81,7 @@ A = ones(5, 3); b = rand(5); b[1] = -1.0;
 (x, stats, resid) = test_crmr(sparse(A), b, λ=1.0e-3);
 show(stats);
 
+# Test b == 0
+(x, stats) = crmr(A, zeros(size(A,1)))
+@test x == zeros(size(A,2))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_lsmr.jl

@@ -22,3 +22,8 @@ end
 (x, stats) = lsmr(full(A), b);
 (x, stats) = lsmr(sparse(full(A)), b);
 show(stats);
+
+# Test b == 0
+(x, stats) = lsmr(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_lsqr.jl

@@ -22,3 +22,8 @@ end
 (x, stats) = lsqr(full(A), b);
 (x, stats) = lsqr(sparse(full(A)), b);
 show(stats);
+
+# Test b == 0
+(x, stats) = lsqr(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"

test/test_minres.jl

@@ -61,3 +61,7 @@ resid = norm(r) / norm(b)
 @test(resid <= 100 * minres_tol);
 @test(stats.solved);
 
+# Test b == 0
+(x, stats) = minres(A, zeros(size(A,1)))
+@test x == zeros(size(A,1))
+@test stats.status == "x = 0 is a zero-residual solution"