activate survey mode in a madgraph script

Asked by Raquel Gomez Ambrosio on 2018-05-17

Dear experts,

I have a madgraph script that generates a process and then usese the syntax

launch process
set param1 1

launch process
set param1 0
set param2 1

and so on....

I noticed that every time I launch, it runs the madevent survey, giving a tentative cross section, and then generates the events, giving the final cross section. Is it possible to add a line in my script so that each time I launch it only runs the survey mode and then goes to the next block without generating the events? (I believe the survey xsec is good enough for me)

Thanks a lot
Raquel

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Raquel Gomez Ambrosio
Solved:
2018-05-17
Last query:
2018-05-17
Last reply:
2018-05-17

Hi,

The easiest is probably to just ask for a single events

i.e. you can do:
> launch process
> set nevents 1
> set param1 scan:[1 if i ==0 else 0 for i in range(2)]
> set param2 scan:[1 if i ==1 else 0 for i in range(2)]

You can run the survey manually via

launch process -i
survey

but then you might not have the possibility to edit the card/having scan/... in that way.
This is why I advise the other method.

Cheers,

Olivier

> On 17 May 2018, at 14:03, Raquel Gomez Ambrosio <email address hidden> wrote:
>
> New question #669178 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/669178
>
> Dear experts,
>
> I have a madgraph script that generates a process and then usese the syntax
>
> launch process
> set param1 1
>
>
> launch process
> set param1 0
> set param2 1
>
>
> and so on....
>
>
> I noticed that every time I launch, it runs the madevent survey, giving a tentative cross section, and then generates the events, giving the final cross section. Is it possible to add a line in my script so that each time I launch it only runs the survey mode and then goes to the next block without generating the events? (I believe the survey xsec is good enough for me)
>
> Thanks a lot
> Raquel
>
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi Olivier, thanks a lot.

Indeed, if I do launch -i I cannot edit the param card anymore after I launched. I will go for option a) then

Best