Reading output from GENPACK

[Laurence Holmes]

Hi I'm trying to adapt the genpack.f file in the GENPACK package to solve my own problems, taking input from a text file which is generated by a Java GUI.

The values for the constraints etc. will be fields in the text file which are read via Fortran I/O.

I'm having some problems returning the output to view in gsview - I'm not sure what I should be editing in the drawsol subroutine.

Currently the Fortran code can be executed by the Java code via cmd, but I'm having trouble getting a solution returned. 

Has anyone tried something like this before?

Any help is much appreciated.

[Ernesto G. Birgin]

Dear Laurence,

Thank you very much for your interest in our work.

Drawsol subroutine generates a metapost file. We compile it using Metapost with the commnad line

mpost solution.mp

It generates a postcript file that we then include in a latex file for visualization. You can find an example of a tex file that includes an image generated in the way I described, for example, here:

http://www.ime.usp.br/~egbirgin/sources/genpack-circles/

I am not sure if this answers your question.

I hope it helps.

Regards,
Ernesto.

[Laurence Holmes]

Hi Ernesto, thanks for your response.

I call all of the command line compilation you mention via Java, and it works fine, just the solution it returns in gsview does not change based on inputs. 

Instead I just get the same shape returned every time.

I think maybe it's a problem with the I/O in the drawsol subroutine to draw the convex shape.

I'm developing an area planning tool for use by architects for a research paper, and was just wondering if anyone else had done similar work calling GENPACK from Java.

Thanks for your help and producing the package, it's great!

Regards,

Laurence

[Ernesto G. Birgin]

Dear Lawrence,

Your application seems to be very interesting. Please, let us know about the progress of your work.

Regarding, your I/O problem, well, I do not know. It may be a problem of gsview, that is not being able to recognize the file has been changed.

Regards,
Ernesto.

[Laurence Holmes]

Hi,

I've now got everything working a bit better thanks - I can return the solution.ps file for any of the test problems via a call from Java.

The only problem I'm having is with using IO in genpack.f to solve my own problem.

I'm not a FORTRAN77 expert - is there anything unexpected in genpack.f which could affect my editing of the subroutines to take input from file? 

From testing I know the defpro subroutine is fine, so I think the problem is in evalw or evaldw.

When I try to select problem 1 at runtime, the command prompt just freezes. 

Again, I appreciate any help!

Anyway, here is what I have for evalw and evaldw:

evalw:

C     LOCAL SCALARS

      double precision tmp,a1,a2,a3,a4,b1,b2,b3,b4,c1,c2,c3,c4 

      if ( probid .eq. 1 ) then

 

         open(unit=8, file="c:\\users\\laurence\\vals.txt")

         read(8, *) a1

         read(8, *) a2

         read(8, *) a3

         read(8, *) a4

         read(8, *) b1

         read(8, *) b2

         read(8, *) b3

         read(8, *) b4

         read(8, *) c1

         read(8, *) c2

         read(8, *) c3

         read(8, *) c4

         close(8)

         w(1) = a1 * p(1) + b1 * p(2) + c1

         w(2) = a2 * p(1) + b2 * p(2) + c2

         w(3) = a3 * p(1) + b3 * p(2) + c3

         w(4) = a4 * p(1) + b4 * p(2) + c4

    ...

evaldw:

      if ( probid .eq. 1 ) then

         open(UNIT=4, FILE="c:\\users\\laurence\\diffs.txt")

         read(4, *) dwdp1(1)

         read(4, *) dwdp1(2)

         read(4, *) dwdp1(3)

         read(4, *) dwdp1(4)

         read(4, *) dwdp2(1)

         read(4, *) dwdp2(2)

         read(4, *) dwdp2(3)

         read(4, *) dwdp2(4)

         close(4)

      ...