errors in using pythia

Asked by Halley Xiong on 2020-09-24

Hi experts,
   I have installed pythia8 , but when I generate a process and launch, choose the switches of programs show that shower = not avail, detector = not avail, and reweight = not avail. Analysis and madspin is normal, which present off. I wonder if it's because installation of pythia is wrong or some other errors. Thanks.
   Best wishes!

Question information

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Status:
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MadGraph5_aMC@NLO Edit question
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Last query:
2020-09-29
Last reply:
2020-10-06

How did you install pythia8?

But yes it indicates that MG5aMC does not find pythia8 executable and/or the mg5topythia8 interface.

Cheers,

Olivier

> On 24 Sep 2020, at 09:05, Halley Xiong <email address hidden> wrote:
>
> New question #693068 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/693068
>
> Hi experts,
> I have installed pythia8 , but when I generate a process and launch, choose the switches of programs show that shower = not avail, detector = not avail, and reweight = not avail. Analysis and madspin is normal, which present off. I wonder if it's because installation of pythia is wrong or some other errors. Thanks.
> Best wishes!
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Halley Xiong (neuromance) said : #2

I install pythia8 according to download page : mg5 > install pythia8 . I occasionally see that ROOT should be installed before Pythia and PGS package, I don't know if it has influence. Thanks.

and they are no complain at the installation time?

Cheers,

Olivier

Halley Xiong (neuromance) said : #4

No, there were no problem at the installation.

ok so if you type (within mg5amc shell)
display options pythia
and then
display options mg

do you see them define or not?
In my case, i have this:
MG5_aMC>display options pythia
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
            pythia-pgs_path : ./pythia-pgs
               pythia8_path : /Users/omattelaer/Documents/HEPTools/pythia8 (user set)

MG5_aMC>display options mg
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
  mg5amc_py8_interface_path : /Users/omattelaer/Documents/HEPTools/MG5aMC_PY8_interface (user set)

If you do can you do a "ls" of each directory
In each case, you should have a install.log file with the details of the installation.

Cheers,

Olivier

Halley Xiong (neuromance) said : #6

Oh, my pythia8_path is None.
MG5_aMC>display options pythia
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
            pythia-pgs_path : ./pythia-pgs
               pythia8_path : None (user set)
MG5_aMC>display options mg
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
  mg5amc_py8_interface_path : None (user set)

But in my HEPTools documents , there exists pythia8 and MG5aMC_PY8_interface documents.

Can you check the content of those directory and the content of the install.log file
in your HepTools directory.

Cheers,

Olivier

> On 24 Sep 2020, at 10:50, Halley Xiong <email address hidden> wrote:
>
> Question #693068 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693068
>
> Halley Xiong gave more information on the question:
> Oh, my pythia8_path is None.
> MG5_aMC>display options pythia
> MadGraph5_aMC@NLO Options
> ----------------
>
> MadEvent Options
> ----------------
>
> Configuration Options
> ---------------------
> pythia-pgs_path : ./pythia-pgs
> pythia8_path : None (user set)
> MG5_aMC>display options mg
> MadGraph5_aMC@NLO Options
> ----------------
>
> MadEvent Options
> ----------------
>
> Configuration Options
> ---------------------
> mg5amc_py8_interface_path : None (user set)
>
> But in my HEPTools documents , there exists pythia8 and
> MG5aMC_PY8_interface documents.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Halley Xiong (neuromance) said : #8

This is mg5amc_py8_interface_install.log :
------------------------------------------------
MG5aMC_PY8_interface compilation output log:
b'g++ MG5aMC_PY8_interface.cc ../lib/libpythia8.a -o MG5aMC_PY8_interface -I/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/hepmc/include\\\n /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface/static_library_dependencies/libHepMC.a -I../include -ldl -fPIC -lstdc++ -DHEPMC2HACK -L../lib -Wl,-rpath,../lib -lpythia8 -ldl -DGZIPSUPPORT -I/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/include -L/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/lib -Wl,-rpath,/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/lib -lz\n'
------------------------------------------------
Successful compilation of the MG5aMC_PY8_interface.

pythia8_install.log:
 Set environment variables
 >> Unpack PYTHIA8
 >> Enter PYTHIA8 directory
 >> Configure PYTHIA8
rm -rf tmp lib
rm -f examples/*Dct.*
rm -f examples/*[0-9]
rm -f examples/weakbosons.lhe
rm -f examples/Pythia8.promc
rm -f examples/hist.root
find . -type f -name Makefile.inc -print0 | xargs -0 rm -f
find . -type f -name "*~" -print0 | xargs -0 rm -f
find . -type f -name "#*" -print0 | xargs -0 rm -f
rm -f share/Pythia8/AUTHORS
rm -f share/Pythia8/COPYING
rm -f share/Pythia8/GUIDELINES
rm -f share/Pythia8/README

Running PYTHIA configuration script. Now is 2020年 09月 21日 星期一 18:19:50 CST
WARNING: Ignoring invalid option "--with-lhapdf6-plugin".

 WARNING: Disabling LHAPDF6 (B - library LHAPDF missing.

This text is too long so I just show the beginning. Is this information enough?
Thanks.

HI,

The interesting part is typically the last bit, but i guess I will not learn anything from it.
But in case, can you include the last 20 lines?

Could you also show the content of ./input/mg5_configuration.txt
and check for the path of pythia8 and mg5amc_py8_interface
Are they correctly defined there?

If they are not could you define them?
If they are, then can you show the printout when you run ./bin/mg5_aMC
it should specify all the configuration that you read, one of them should remove it.
(one option is that you have a second configuration file that overwrite the first one)

Cheers,

Olivier

> On 24 Sep 2020, at 11:05, Halley Xiong <email address hidden> wrote:
>
> Question #693068 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693068
>
> Status: Answered => Open
>
> Halley Xiong is still having a problem:
> This is mg5amc_py8_interface_install.log :
> ------------------------------------------------
> MG5aMC_PY8_interface compilation output log:
> b'g++ MG5aMC_PY8_interface.cc ../lib/libpythia8.a -o MG5aMC_PY8_interface -I/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/hepmc/include\\\n /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface/static_library_dependencies/libHepMC.a -I../include -ldl -fPIC -lstdc++ -DHEPMC2HACK -L../lib -Wl,-rpath,../lib -lpythia8 -ldl -DGZIPSUPPORT -I/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/include -L/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/lib -Wl,-rpath,/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/zlib/lib -lz\n'
> ------------------------------------------------
> Successful compilation of the MG5aMC_PY8_interface.
>
> pythia8_install.log:
> Set environment variables
>>> Unpack PYTHIA8
>>> Enter PYTHIA8 directory
>>> Configure PYTHIA8
> rm -rf tmp lib
> rm -f examples/*Dct.*
> rm -f examples/*[0-9]
> rm -f examples/weakbosons.lhe
> rm -f examples/Pythia8.promc
> rm -f examples/hist.root
> find . -type f -name Makefile.inc -print0 | xargs -0 rm -f
> find . -type f -name "*~" -print0 | xargs -0 rm -f
> find . -type f -name "#*" -print0 | xargs -0 rm -f
> rm -f share/Pythia8/AUTHORS
> rm -f share/Pythia8/COPYING
> rm -f share/Pythia8/GUIDELINES
> rm -f share/Pythia8/README
>
> Running PYTHIA configuration script. Now is 2020年 09月 21日 星期一 18:19:50 CST
> WARNING: Ignoring invalid option "--with-lhapdf6-plugin".
>
>  WARNING: Disabling LHAPDF6 (B - library LHAPDF missing.
>
> This text is too long so I just show the beginning. Is this information enough?
> Thanks.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Halley Xiong (neuromance) said : #10

Ok, this is the last lines of pythia8_install.log :

ar: `u' 修饰符被忽略,因为 `D' 为默认(参见 `U')
cp AUTHORS share/Pythia8/AUTHORS
cp COPYING share/Pythia8/COPYING
cp GUIDELINES share/Pythia8/GUIDELINES
cp README share/Pythia8/README
cp Makefile.inc share/Pythia8/../../examples/Makefile.inc
mkdir -p /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//bin /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//include /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//lib /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//share/Pythia8
rm -f /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//lib/libpythia8.so
rsync -a bin/* /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//bin --exclude .svn
rsync -a include/* /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//include --exclude .svn
rsync -a lib/* /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//lib --exclude .svn
rsync -a share/Pythia8/* /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//share/Pythia8 --exclude .svn
rsync -a examples /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8//share/Pythia8 --exclude .svn
 Finished PYTHIA8 installation

The following is ./input/mg5_configuration.txt:

#! Prefered Fortran Compiler
#! If None: try to find g77 or gfortran on the system
#!
# fortran_compiler = None
# f2py_compiler_py2 = None
# f2py_compiler_py3 = None

#! Prefered C++ Compiler
#! If None: try to find g++ or clang on the system
#!
# cpp_compiler = None

#! Prefered Text Editor
#! Default: use the shell default Editor
#! or try to find one available on the system
#! Be careful: Only shell based editor are allowed
# text_editor = None

#! Prefered WebBrower
#! If None: try to find one available on the system
# web_browser = None

#! Prefered PS viewer
#! If None: try to find one available on the system
# eps_viewer = None

#! Time allowed to answer question (if no answer takes default value)
#! 0: No time limit
# timeout = 60

#! Pythia8 path.
#! Defines the path to the pythia8 installation directory (i.e. the
#! on containing the lib, bin and include directories) .
#! If using a relative path, that starts from the mg5 directory
pythia8_path = /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8 #

#! MG5aMC_PY8_interface path
#! Defines the path of the C++ driver file that is used by MG5_aMC to
#! steer the Pythia8 shower.
#! Can be installed directly from within MG5_aMC with the following command:
#! MG5_aMC> install mg5amc_py8_interface
mg5amc_py8_interface_path = /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface #

#! Herwig++/Herwig7 paths
#! specify here the paths also to HepMC ant ThePEG
#! define the path to the herwig++, thepeg and hepmc directories.
#! paths can be absolute or relative from mg5 directory
#! WARNING: if Herwig7 has been installed with the bootstrap script,
#! then please set thepeg_path and hepmc_path to the same value as
#! hwpp_path
# hwpp_path =
# thepeg_path =
# hepmc_path =

#! Control when MG5 checks if he is up-to-date.
#! Enter the number of day between two check (0 means never)
#! A question is always asked before any update
# auto_update = 7

This is the printout when I run ./bin/mg5_aMC:

************************************************************
* *
* W E L C O M E to *
* M A D G R A P H 5 _ a M C @ N L O *
* *
* *
* * * *
* * * * * *
* * * * * 5 * * * * *
* * * * * *
* * * *
* *
* VERSION 2.8.0 2020-08-21 *
* *
* The MadGraph5_aMC@NLO Development Team - Find us at *
* https://server06.fynu.ucl.ac.be/projects/madgraph *
* and *
* http://amcatnlo.web.cern.ch/amcatnlo/ *
* *
* Type 'help' for in-line help. *
* Type 'tutorial' to learn how MG5 works *
* Type 'tutorial aMCatNLO' to learn how aMC@NLO works *
* Type 'tutorial MadLoop' to learn how MadLoop works *
* *
************************************************************
load MG5 configuration from input/mg5_configuration.txt
fastjet-config does not seem to correspond to a valid fastjet-config executable (v3+). We will use fjcore instead.
 Please set the 'fastjet'variable to the full (absolute) /PATH/TO/fastjet-config (including fastjet-config).
 MG5_aMC> set fastjet /PATH/TO/fastjet-config

lhapdf-config does not seem to correspond to a valid lhapdf-config executable.
Please set the 'lhapdf' variable to the (absolute) /PATH/TO/lhapdf-config (including lhapdf-config).
Note that you can still compile and run aMC@NLO with the built-in PDFs
 MG5_aMC> set lhapdf /PATH/TO/lhapdf-config

/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/lhapdf6_py3/bin/lhapdf-config does not seem to correspond to a valid lhapdf-config executable.
Please set the 'lhapdf' variable to the (absolute) /PATH/TO/lhapdf-config (including lhapdf-config).
Note that you can still compile and run aMC@NLO with the built-in PDFs
 MG5_aMC> set lhapdf /PATH/TO/lhapdf-config

Using default text editor "vi". Set another one in ./input/mg5_configuration.txt
Using default eps viewer "evince". Set another one in ./input/mg5_configuration.txt
Using default web browser "firefox". Set another one in ./input/mg5_configuration.txt
Loading default model: sm
INFO: Restrict model sm with file models/sm/restrict_default.dat .
INFO: Run "set stdout_level DEBUG" before import for more information.
INFO: Change particles name to pass to MG5 convention
Defined multiparticle p = g u c d s u~ c~ d~ s~
Defined multiparticle j = g u c d s u~ c~ d~ s~
Defined multiparticle l+ = e+ mu+
Defined multiparticle l- = e- mu-
Defined multiparticle vl = ve vm vt
Defined multiparticle vl~ = ve~ vm~ vt~
Defined multiparticle all = g u c d s u~ c~ d~ s~ a ve vm vt e- mu- ve~ vm~ vt~ e+ mu+ t b t~ b~ z w+ h w- ta- ta+

Thanks for your help.

Everything seems fine

Do you have the file
/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8/include/Pythia8/Pythia.h
and also the following one:
/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface//MG5aMC_PY8_interface

Cheers,

Olivier

> On 24 Sep 2020, at 11:50, Halley Xiong <email address hidden> wrote:
>
> mg5amc_py8_interface_path = /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface #

Halley Xiong (neuromance) said : #12

Yes, I can find these two files. Do I need to show the details of the files?

Then I start to have no clue sorry.

My last option is to try to force the setting of pythia8 by settting
set mg5amc_py8_interface_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface
set pythia8_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8

Hoping that this will solve the issue (but not very confident that it will)

Cheers,

Olivier

Halley Xiong (neuromance) said : #14

Sorry, I'm a little confused. These two files have already in the path you pointed out, why setting like pythia8_path in that way?
Thanks for your time. The problem puzzled me for several days and take you a lot of time too. I try to search other similar questions but I can't find exactly the same.

Sorry, I'm a little confused. These two files have already in the path you pointed out, why setting like pythia8_path in that way?

You are perfectly right. This is a foolish attempt.
The point is that I do not understand what's going on. If I would have access to the machine, I would start to put a lot of print statement inside the code to understand why and when the setting to those two lines are reset to zero.
But since I do not the best I can suggest is such foolish attempt who, by luck, might reset the value after the start of the code.

So maybe I can be more explicit about the idea:
can you do the following
./bin/mg5_aMC
set mg5amc_py8_interface_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface
display options mg5amc_py8_interface_path

(and the same for the second option).
This is actually instructive since if you do not have the display it means that the issue is inside the set function and if you do, then it might be a way to have it working (even if this means you have to reset it for each job).

> I try to search other similar questions but I can't find exactly the same.

Yes this type of issue does not pop very often.

Cheers,

Olivier

Halley Xiong (neuromance) said : #16

Thanks Olivier, I have tried the way you said. Here is the result of the set :

MG5_aMC>set mg5amc_py8_interface_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface
save options mg5amc_py8_interface_path
save configuration file to /home/xhy/MadGraph5/MG5_aMC_v2_8_0/input/mg5_configuration.txt
MG5_aMC>display options mg5amc_py8_interface_path
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
  mg5amc_py8_interface_path : /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface (user set)

and

MG5_aMC>set pythia8_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8
save options pythia8_path
save configuration file to /home/xhy/MadGraph5/MG5_aMC_v2_8_0/input/mg5_configuration.txt
MG5_aMC>display options pythia8_path
                          MadGraph5_aMC@NLO Options
                          ----------------

                         MadEvent Options
                          ----------------

                      Configuration Options
                      ---------------------
               pythia8_path : /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8 (user set)

I tried to launch a process I have generated before, but the shower = not avail still. Should I generate a new process or something else?

Halley Xiong (neuromance) said : #17

Hi Olivier, I have generated a new process, but the problem is still there.

Just to be sure did you run everything in the same session?

so something like
set mg5amc_py8_interface_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface
set pythia8_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8
generate p p > t t~
output
launch

or

set mg5amc_py8_interface_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/MG5aMC_PY8_interface
set pythia8_path /home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8
launch PATH

The fact that you have the path save here is a encouraging sign. I will have to check the question itself to check if additional check of the validity of the path is performed at that stage or not.

Cheers,

Olivier

Halley Xiong (neuromance) said : #19

Yes, I have set the path then I generate a process and launch, but the shower program is still not avail.

I also see that i sometimes check the existence of this path:
/home/xhy/madgraph/MG5_aMC_v2_8_0/HEPTools/pythia8/bin/pythia8-config

One other idea is that this can be a python3 specific issue.
what is the output of python3 --version ?
can you try to run with python2.7 to see if it works with that version of python?
python27 ./bin/mg5aMC

Cheers,

Olivier

Halley Xiong (neuromance) said : #21

Thanks Olivier,
My python3 version is 3.8.2. I don't know if python2.7 can be set to be default compiler, I've tried to do that but then my computer met some problems . Then I learn that Python 2.7 has been moved to Universe and is not included by default in the new installation in ubuntu20.

Halley Xiong (neuromance) said : #22

Oh I'm sorry, just now I check my python version is Python 2.7.18rc1. That's a bit weird cause previously I typed python version didn't output results, only input python2/3 version could output its version. So how can I know the version of python when I run madgraph?
Thanks,
Halley

Hi,

I would certainly not recommend to put 2.7 as default python version.
But it should be possible to install it from source (now this is likely not worhted the time to do that)

> . Then I learn that Python 2.7 has been moved to Universe and is not included by default in the new installation in ubuntu20.

Indeed python27 is now out of support. 2.8.0 is our first non beta release supporting python3.
And adding such support was quite challenging, so one wild guess is that this is related in some way.

I will try to install 3.8.2 to see if I can reproduce the issue.
But Otherwise, the only option that remains is to run pythia8 by hand instead that via MG5aMC

Cheers,

Olivier

> On 29 Sep 2020, at 09:41, Halley Xiong <email address hidden> wrote:
>
> Question #693068 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693068
>
> Halley Xiong posted a new comment:
> Thanks Olivier,
> My python3 version is 3.8.2. I don't know if python2.7 can be set to be default compiler, I've tried to do that but then my computer met some problems . Then I learn that Python 2.7 has been moved to Universe and is not included by default in the new installation in ubuntu20.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

In 2.8.0, we run the "python3" executable.

if you want to run with python2.7
you have to run
python2 ./bin/mg5_aMC
or
python27 ./bin/mg5_aMC
or
python ./bin/mg5_aMC

Cheers,

Olivier

Halley Xiong (neuromance) said : #25

Hello, Olivier
I've been trying to follow your method to run python2 ./bin/mg5_aMC, but there appeared a prompt :
madgraph requires the six module.
but I have already installed six module, I searched on the internet but still cannot get the answer.
I think your suggestion of run pyhia8 by hand is feasible, cause I meet lots of troubles when trying to run pythia8 in mg5.
Thank you for spending so much time helping me solve this question.
Best wishes,
Halley

To install six for python2, you likely need
sudo pip2 install six
or
pip2 install six --user

You probably have install six for python3 and not for python2

Cheers,

Olivier

> On 6 Oct 2020, at 17:41, Halley Xiong <email address hidden> wrote:
>
> Question #693068 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/693068
>
> Halley Xiong posted a new comment:
> Hello, Olivier
> I've been trying to follow your method to run python2 ./bin/mg5_aMC, but there appeared a prompt :
> madgraph requires the six module.
> but I have already installed six module, I searched on the internet but still cannot get the answer.
> I think your suggestion of run pyhia8 by hand is feasible, cause I meet lots of troubles when trying to run pythia8 in mg5.
> Thank you for spending so much time helping me solve this question.
> Best wishes,
> Halley
>
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> contact for MadGraph5_aMC@NLO.

Halley Xiong (neuromance) said : #27

Yes, you are right. Now I have installed six for python2 and run mg5_aMC with python2 successfully. But after I set the pythia8_path and generate a process, launch the file , I still can not switch "shower" and "detector" to another value via number because shower = Not Avail and detector = Not Avail.

Can you help with this problem?

Provide an answer of your own, or ask Halley Xiong for more information if necessary.

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