fixed the issue and moved rNorm

Author: farhadrclass

src/cr.jl

@@ -150,27 +150,28 @@ kwargs_cr = (:M, :ldiv, :radius, :linesearch, :γ, :atol, :rtol, :itmax, :timema
     end
     MisI && kcopy!(n, r, p)  # r ← p
     MisI || mulorldiv!(r, M, p, ldiv)
-    mul!(Ar, A, r)
-    ρ = kdotr(n, r, Ar)
-
+    
     rNorm = knorm_elliptic(n, r, p)  # ‖r‖
     history && push!(rNorms, rNorm)  # Values of ‖r‖
 
     if rNorm == 0
       stats.niter = 0
       stats.solved, stats.inconsistent = true, false
       stats.timer = start_time |> ktimer
-      stats.status = "x = 0 is a zero-residual solution"
+      stats.status = "x is a zero-residual solution"
       history && push!(ArNorms, zero(T))
       solver.warm_start = false
       return solver
     end
+
+    mul!(Ar, A, r)
+    ρ = kdotr(n, r, Ar)
 
     if ρ == 0
       stats.niter = 0
       stats.solved, stats.inconsistent = true, false
       stats.timer = start_time |> ktimer
-      stats.status = "0 is a zero-curvature direction"
+      stats.status = "b is a zero-curvature direction"
       history && push!(ArNorms, zero(T))
       solver.warm_start = false
       linesearch && kcopy!(n, x, b)  # x ← b

test/test_cr.jl

@@ -52,7 +52,7 @@
       A, b = zero_rhs(FC=FC)
       (x, stats) = cr(A, b)
       @test norm(x) == 0
-      @test stats.status == "x = 0 is a zero-residual solution"
+      @test stats.status == "x is a zero-residual solution"
 
       # Test with Jacobi (or diagonal) preconditioner
       A, b, M = square_preconditioned(FC=FC)
@@ -68,7 +68,7 @@
       @test stats.status == "nonpositive curvature"
 
       # Test Linesearch which would stop on the first call since A is negative definite
-      A, b = indefinite_system(FC=FC)
+      A, b = symmetric_indefinite(FC=FC; shift = 5)
       x, stats = cr(A, b, linesearch=true)
       @test stats.status == "nonpositive curvature"
       @test stats.niter == 0
@@ -78,14 +78,14 @@
       # Test when b^TAb=0 and linesearch is true
       A, b = system_zero_quad(FC=FC)
       x, stats = cr(A, b, linesearch=true)
-      @test stats.status == "0 is a zero-curvature direction"
+      @test stats.status == "b is a zero-curvature direction"
       @test all(x .== b)
       @test stats.solved == true
 
       # Test when b^TAb=0 and linesearch is false
       A, b = system_zero_quad(FC=FC)
       x, stats = cr(A,b, linesearch=false)
-      @test stats.status == "0 is a zero-curvature direction"
+      @test stats.status == "b is a zero-curvature direction"
       @test norm(x) == zero(FC)
       @test stats.solved == true
 

test/test_utils.jl

@@ -14,29 +14,13 @@ function symmetric_definite(n :: Int=10; FC=Float64)
 end
 
 # Symmetric and indefinite systems.
-function symmetric_indefinite(n :: Int=10; FC=Float64)
+function symmetric_indefinite(n :: Int=10; FC=Float64,  shift=0)
   α = FC <: Complex ? FC(im) : one(FC)
-  A = spdiagm(-1 => α * ones(FC, n-1), 0 => ones(FC, n), 1 => conj(α) * ones(FC, n-1))
+  A = spdiagm(-1 => α * ones(FC, n-1), 0 => ones(FC, n), 1 => conj(α) * ones(FC, n-1))- shift * eye(n)
   b = A * FC[1:n;]
   return A, b
 end
 
-
-# Symmetric and indefinite system with negative curvature.
-# need this to test CR with Linesearch and nonpositive curvature at the first iteration
-function indefinite_system(n::Int=10; FC=Float64, shift=5)
-  α = FC <: Complex ? FC(im) : one(FC)
-  # Build the tridiagonal matrix with 1's on the diagonal and α on the off-diagonals, and force negative curvature.
-  A = spdiagm(
-          -1 => α * ones(FC, n-1),
-           0 => ones(FC, n),
-           1 => conj(α) * ones(FC, n-1)
-      ) - shift * eye(n)
-  
-  b = A * FC[1:n;]  
-  return A, b
-end
-
 """
     system_zero_quad(n::Int=2; FC=Float64)