matrix element compilation error

In which version?

Olivier

> On 11 Aug 2021, at 14:50, Hans Zippert <email address hidden> wrote:
>
> New question #698327 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/698327
>
> Hi,
>
> I was trying to evaluate the matrix elemet for the process u u~ > t t~:
>
> generate u u~ > t t~
> output standalone testdir
> launch
>
> I get the following error message:
>
> The compilation fails with the following output message:
> gfortran -w -fPIC -ffixed-line-length-132 -c -o matrix.o matrix.f
> gfortran -w -fPIC -ffixed-line-length-132 -c -o check_sa.o check_sa.f
> check_sa.f:232:27:
>
> 232 | SAVE TWOPI, PO2LOG, Z(2)
> | 1
> Error: Syntax error in SAVE statement at (1)
> make: *** [<builtin>: check_sa.o] Error 1
> Please try to fix this compilations issue and retry.
>
> Is there something I can do to fix this problem?
> Besides, if I compute the cross section (i.e. dropping the word "standalone"), it works perfectly.
>
> Thanks in advance!
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

When I start MadGraph5 via

/bin/mg5_aMC

it says VERSION 3.1.1 2021-05-28

So here is the patch that you can apply to fix that issue:

=== modified file 'madgraph/iolibs/template_files/check_sa.f'
--- madgraph/iolibs/template_files/check_sa.f 2021-04-27 14:36:52 +0000
+++ madgraph/iolibs/template_files/check_sa.f 2021-07-28 14:12:54 +0000
@@ -229,7 +229,7 @@
      . E(NEXTERNAL-NINCOMING),V(NEXTERNAL-NINCOMING),IWARN(5)
       SAVE ACC,ITMAX,IBEGIN,IWARN
       DATA ACC/1.D-14/,ITMAX/6/,IBEGIN/0/,IWARN/5*0/
- SAVE TWOPI, PO2LOG, Z(2)
+ SAVE TWOPI, PO2LOG, Z
 *
 * INITIALIZATION STEP: FACTORIALS FOR THE PHASE SPACE WEIGHT
       IF(IBEGIN.NE.0) GOTO 103

Cheers,

Olivier

> On 11 Aug 2021, at 15:11, Hans Zippert <email address hidden> wrote:
>
> Question #698327 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698327
>
> Hans Zippert posted a new comment:
> When I start MadGraph5 via
>
> /bin/mg5_aMC
>
> it says VERSION 3.1.1 2021-05-28
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Thanks for the answer! Unfortunately, after applying the patch (i.e. replacing seven lines in the file madgraph/iolibs/template_files/check_sa.f by the ones above), I get another error:

str : A compilation Error occurs when trying to compile /home/MG5_aMC_v3_1_1/testdir/SubProcesses/P1_uux_ttx.
 The compilation fails with the following output message:
     gfortran -w -fPIC -ffixed-line-length-132 -c -o matrix.o matrix.f
     gfortran -w -fPIC -ffixed-line-length-132 -c -o check_sa.o check_sa.f
     check_sa.f:232:1:

       232 | - SAVE TWOPI, PO2LOG, Z(2)
           | 1
     Error: Non-numeric character in statement label at (1)
     check_sa.f:232:23:

       232 | - SAVE TWOPI, PO2LOG, Z(2)
           | 1
     Error: Syntax error in SAVE statement at (1)
     check_sa.f:233:1:

       233 | + SAVE TWOPI, PO2LOG, Z
           | 1
     Error: Non-numeric character in statement label at (1)
     check_sa.f:234:3:

       234 | *
           | 1
     Error: Non-numeric character in statement label at (1)
     check_sa.f:235:3:

       235 | * INITIALIZATION STEP: FACTORIALS FOR THE PHASE SPACE WEIGHT
           | 1
     Error: Non-numeric character in statement label at (1)
     make: *** [<builtin>: check_sa.o] Error 1

After restarting the computer, everything works now! Thanks a lot for your patience and competence and have a nice evening!

Thanks Olivier Mattelaer, that solved my question.