fix test svd (related to signs of singular values)

Author: jvdp1

test/linalg/test_linalg_svd.fypp

@@ -93,7 +93,7 @@ module test_linalg_svd
         if (allocated(error)) return        
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return             
-        call check(error, all(abs(u-u_sol)<=tol) .or. all(abs(u+u_sol)<=tol), test//': U')
+        call check(error, all(abs(abs(u)-abs(u_sol))<=tol), test//': U')
         if (allocated(error)) return             
 
         !> [S, U]. Overwrite A matrix
@@ -104,7 +104,7 @@ module test_linalg_svd
         if (allocated(error)) return        
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return             
-        call check(error, all(abs(u-u_sol)<=tol) .or. all(abs(u+u_sol)<=tol), test//': U')
+        call check(error, all(abs(abs(u)-abs(u_sol))<=tol), test//': U')
         if (allocated(error)) return            
 
         !> [S, U, V^T]
@@ -116,9 +116,9 @@ module test_linalg_svd
         if (allocated(error)) return        
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return             
-        call check(error, all(abs(u-u_sol)<=tol) .or. all(abs(u+u_sol)<=tol), test//': U')
+        call check(error, all(abs(abs(u)-abs(u_sol))<=tol), test//': U')
         if (allocated(error)) return           
-        call check(error, all(abs(vt-vt_sol)<=tol) .or. all(abs(vt+vt_sol)<=tol), test//': V^T')
+        call check(error, all(abs(abs(vt)-abs(vt_sol))<=tol), test//': V^T')
         if (allocated(error)) return           
 
         !> [S, V^T]. Do not overwrite A matrix
@@ -130,7 +130,7 @@ module test_linalg_svd
         if (allocated(error)) return        
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return             
-        call check(error, all(abs(vt-vt_sol)<=tol) .or. all(abs(vt+vt_sol)<=tol), test//': V^T')
+        call check(error, all(abs(abs(vt)-abs(vt_sol))<=tol), test//': V^T')
         if (allocated(error)) return   
 
         !> [S, V^T]. Overwrite A matrix
@@ -141,7 +141,7 @@ module test_linalg_svd
         if (allocated(error)) return        
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return             
-        call check(error, all(abs(vt-vt_sol)<=tol) .or. all(abs(vt+vt_sol)<=tol), test//': V^T')
+        call check(error, all(abs(abs(vt)-abs(vt_sol))<=tol), test//': V^T')
         if (allocated(error)) return           
 
         !> [U, S, V^T].
@@ -151,11 +151,11 @@ module test_linalg_svd
         test = '[U, S, V^T]'
         call check(error,state%ok(),test//': '//state%print())
         if (allocated(error)) return        
-        call check(error, all(abs(u-u_sol)<=tol) .or. all(abs(u+u_sol)<=tol), test//': U')
+        call check(error, all(abs(abs(u)-abs(u_sol))<=tol), test//': U')
         if (allocated(error)) return                   
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return     
-        call check(error, all(abs(vt-vt_sol)<=tol) .or. all(abs(vt+vt_sol)<=tol), test//': V^T')
+        call check(error, all(abs(abs(vt)-abs(vt_sol))<=tol), test//': V^T')
         if (allocated(error)) return             
 
         !> [U, S, V^T]. Partial storage -> compare until k=2 columns of U rows of V^T
@@ -167,11 +167,11 @@ module test_linalg_svd
         test = '[U, S, V^T], partial storage'
         call check(error,state%ok(),test//': '//state%print())
         if (allocated(error)) return        
-        call check(error, all(abs(u(:,:2)-u_sol(:,:2))<=tol) .or. all(abs(u(:,:2)+u_sol(:,:2))<=tol), test//': U(:,:2)')
+        call check(error, all(abs(abs(u(:,:2))-abs(u_sol(:,:2)))<=tol), test//': U(:,:2)')
         if (allocated(error)) return                   
         call check(error, all(abs(s-s_sol)<=tol), test//': S')
         if (allocated(error)) return     
-        call check(error, all(abs(vt(:2,:)-vt_sol(:2,:))<=tol) .or. all(abs(vt(:2,:)+vt_sol(:2,:))<=tol), test//': V^T(:2,:)')
+        call check(error, all(abs(abs(vt(:2,:))-abs(vt_sol(:2,:)))<=tol), test//': V^T(:2,:)')
         if (allocated(error)) return           
 
     end subroutine test_svd_${ri}$