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[colt1954]

I am having a problem I define a 8x11 arrays FX(j,nrpm) etc I assign values in a double loop. But when I try to write the same array out to file, slightly further down the code, using another double loop reversing the order, using j and n as the loop variables it complains that they are undefined variables etc?? I am of course now using 11x8 in the reversal.

here is a subset of the code in question its part of a bigger subroutine loop where NRPM is incremented - note I am reversing the order its written out
ie I want J tabled with NRPM (N) incremented, then stepping J+1 increment then NRPM incremented again.

DO J=1,8
DO M=2,512
IF(ABS(THETA(2,M)-(RPM*J/120)).LT.0.01)THEN
FX(J,NRPM)=ABS(GENG(31,M))
FY(J,NRPM)=ABS(GENG(32,M))
FZ(J,NRPM)=ABS(GENG(33,M))
MX(J,NRPM)=ABS(GENG(34,M))
MY(J,NRPM)=ABS(GENG(35,M))
MZ(J,NRPM)=ABS(GENG(36,M))
ENDIF
ENDDO
ENDDO
IF(NRPM.EQ.11)THEN
DO J=1,8

DO N=1,NRPM
ESP=RPMIN+(N-1)*RPMI
EO=J*0.5
WRITE(*,*)ESP,EO,ESP*j/120,FX(J,N),FY(J,N),FZ(J,N),MX(J,N),MY(J,N),MZ(J,N)
ENDDO
ENDDO
ENDIF

Basically it does not recognise the FX(J,N) etc variables? error 112 reference to undefined variable etc...

[JohnHorspool]

Where you assign values to FX as in FX(J,NRPM)=ABS(GENG(31,M)) the second index is fixed at NRPM so for the loop M=2,512 you are just continuously overwriting the same cell.

Whilst when you try to write out the array contents you are attempting to do this with the second index varying from 1 to NRPM. Cells with indeces 1 to NRPM-1 have not been populated, hence the error message.
_________________
John Horspool
Roshaz Software Ltd.
Gloucestershire

[colt1954]

[colt1954]

if i try to print out two Fz array values beyond the initial do loops its again says its undefined, so its losing its values not sure why?

FX(J,NRPM)=ABS(GENG(31,M))
FY(J,NRPM)=ABS(GENG(32,M))
FZ(J,NRPM)=ABS(GENG(33,M))
MX(J,NRPM)=ABS(GENG(34,M))
MY(J,NRPM)=ABS(GENG(35,M))
MZ(J,NRPM)=ABS(GENG(36,M))
! PRINT *,j,nrpm, fz(j,nrpm) - assigns ok here !!
ENDIF
ENDDO
ENDDO
print *,fz(1,1),fz(1,2) - undefined here !!!

[davidb]

Your code is very difficult to understand.

Can you provide details of what you are trying to do (rather than code that doesn't work)?

Sometimes, the only way to make progress is to throw away what you have and start again.


Whatever the value of NRPM is (but actually it must be 11 to get the printout), you are only setting up one column of the arrays FX, FY etc.

You therefore get an error when you try to access the other columns since
they are undefined.
_________________
Programmer in: Fortran 77/95/2003/2008, C, C++ (& OpenMP), java, Python, Perl

[JohnHorspool]

There is nothing in this block of code that increments the value of NRPM !

[colt1954]

[davidb]

If the code you have provided in your first post is in a subroutine then the values you set up for a given value of NRPM will be lost when the subroutine exits (depending on whether you used the SAVE attribute or SAVE statement or not), so when the next call is made with NRPM incremented an "undefined" error will occur.

Can we see all the code or enough to work out what you have done?

We need to see where and how each variable is declared, and what the scope of each variable is.

Its almost certainly an error in the code, rather than a FTN95 error.
_________________
Programmer in: Fortran 77/95/2003/2008, C, C++ (& OpenMP), java, Python, Perl

[davidb]

In the last program you posted you have a STOP between the last END DO and the END IF.

But you don't have this in the first code!!

Perhaps you have started again!
_________________
Programmer in: Fortran 77/95/2003/2008, C, C++ (& OpenMP), java, Python, Perl

[colt1954]

[colt1954]

[davidb]

Don't post it if its very big.

Try

real, save :: FX(10,11), FY(10,11), ...

etc but use the dimensions you have now.

or you can add the line

save FX, FY, ...
_________________
Programmer in: Fortran 77/95/2003/2008, C, C++ (& OpenMP), java, Python, Perl

[davidb]

I modified your program so it has a subroutine. Does your real program look like this.

[colt1954]

Hi David if you were near by I'd hug you!!!

I have spent hours on this....yes your right I have got round it using common block etc, ok old fashioned I know but much of my programme is based on them. Have not looked at this programme for ages so a little rusty I guess....

Thanks again David have a nice weekend.

ps have just seen your save command might give that a whirl too it looks simpler than common block approach etc

[davidb]

Good to know you have a way forward
_________________
Programmer in: Fortran 77/95/2003/2008, C, C++ (& OpenMP), java, Python, Perl