writing a matrix 5x5 in an output file (.txt)

[carlasilva]

How do I programme writing a matrix 5x5 in an output file (.txt)?
I would like to see the original matrix format, but I had tried and in the output file appears all the numbers in a single column.

Thank you for your help!

 

[PAndersen]

DIMENSION M(5,5)
OPEN(10,FILE='M.TXT')
C DEFINE THE MATRIX ......
C ........
DO 20 I = 1 , 5
20 WRITE(10,22) (M(I,J),J=1,5)
22 FORMAT(1H ,5I5)
CLOSE (10)
END

 

[BlatherSkyte]

Hey~!

I'm trying to do the samne thing but I want the user to be able to define how large the matrix is going to be. That is, I want to be able to format the output and still have it print in a matrix form once the user tells the program how large - # of rows and columns - the nput and output matrices have

Is there a way to do this without using the default (*) format specifier?

 

[PAndersen]

Set the dimension to (at least) the maximum to be used.
Instead of upper limit (5) of I and J , enter the maximum : READ(*,*) IMAX,JMAX and use
DO 20I=1,IMAX
20 WRITE(20,22)(M(I,J),J=1,JMAX)