f90: Lazy to check whether your matrix is symetric or not! Try this program. The program will tell you where the matrix is asymetric. *.exe and *.out are the Windows and Linux executables.

symetric.exe

symetric.f90

PROGRAM symetric

IMPLICIT NONE

! Declarations

INTEGER:: i, j, n, check1, check2=0
REAL,DIMENSION(:,:),ALLOCATABLE:: x
 CHARACTER(20):: input, exiit

! Opening prints

PRINT*,
PRINT*,
PRINT*, 'This program is written by Mohammad A. Nilforooshan.'
PRINT*, 'All rights reserved.'
PRINT*, 'http://sites.google.com/site/mannprofile/'

! ASK for the input file, open and check it

PRINT*,
PRINT*,
PRINT*, 'Type the name of the input file.'
READ*, input
OPEN(UNIT=10, FILE=input, STATUS='OLD', IOSTAT=check1)

IF (check1/=0) THEN
    PRINT*,
    PRINT*,
    PRINT*, 'Error reading the input file'
    STOP
END IF

! Ask for the size of the matrix

PRINT*,
PRINT*,
PRINT*, 'Insert the size of the square matrix.'
READ*, n

! Read the matrix

ALLOCATE(x(n,n))
READ(10,*) ((x(i,j),j=1,n),i=1,n)

! Check where the matrix is asymetric

PRINT*,
DO i=1,n-1
    j=i+1
    IF (x(i,j)/=x(j,i)) THEN
        PRINT*, 'See (',i,',',j,'),(',j,',',i,')'
        check2=check2+1
    END IF
END DO

! Final report

PRINT*,
IF (check2==0) THEN
    PRINT*, 'The matric is symetric.'
    ELSE
    PRINT*, 'The matrix is asymetric.'
END IF

! Finished

PRINT*,
PRINT*,
PRINT*, 'Press any key to exit.'
READ*, exiit

IF (exiit=='a') THEN
GO TO 77
END IF

77 END PROGRAM symetric

symetric.out