increase cross section output precision

Asked by Tania Robens on 2018-02-27

Hi

a very simple question: I have a run where in the result.dat file I get something like

0.10195E-01 0.37221E-06 0.00000E+01 40952080 0 0 2086886 0.00000E+01 0.00000E+01 0.10195E-01 0.00000E+01 0.00000E+01 0

I would like to increase the number of significant digits in the output for the total cross section, ie instead of

0.10195e-1 i would like to see something like

0.1019xxx, e.g. 0.101948339 (or whatever is the outcome), to see at least the digit which is on the order of the error (.000004e-1)

I might have asked the question before (..) but cant find the answer at the moment - sorry

Let me know

Thanks Best Tania

Question information

Language:
English Edit question
Status:
Expired
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Last query:
2018-02-27
Last reply:
2018-03-15

Hi,

You can try to edit the following line:

in file Template/LO/Source/dsample.f
around line 213, you have the following line:

      if (icor .eq. 0) then
         write(66,'(3e12.5,2i9,i5,i9,e10.3,e12.5,3e13.5,i9)')tmean,tsigma, 0.0,
     & kevent, nw, cur_it-1, nun, nun/max(tmean,1d-99), twgt, trmean,
     & maxwgt, th_maxwgt, th_nunwgt
      else
         write(66,'(3e12.5,2i9,i5,i9,e10.3,e12.5,3e13.5,i9)')tmean,0.0,tsigma,
     & kevent, nw, cur_it-1, nun, nun/max(tmean,1d-99), twgt, trmean,
     & maxwgt, th_maxwgt, th_nunwgt
      endif

where you can change the line formatting as you want.
Be careful that such line are also read from the code so changing them might create crash depending if you
only run the survey or not.

Cheers,

Olivier

> On 27 Feb 2018, at 16:32, Tania Robens <email address hidden> wrote:
>
> New question #665039 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/665039
>
> Hi
>
> a very simple question: I have a run where in the result.dat file I get something like
>
> 0.10195E-01 0.37221E-06 0.00000E+01 40952080 0 0 2086886 0.00000E+01 0.00000E+01 0.10195E-01 0.00000E+01 0.00000E+01 0
>
> I would like to increase the number of significant digits in the output for the total cross section, ie instead of
>
> 0.10195e-1 i would like to see something like
>
> 0.1019xxx, e.g. 0.101948339 (or whatever is the outcome), to see at least the digit which is on the order of the error (.000004e-1)
>
> I might have asked the question before (..) but cant find the answer at the moment - sorry
>
> Let me know
>
> Thanks Best Tania
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Tania Robens (tania-robens) said : #2

do i have to recompile ?

Launchpad Janitor (janitor) said : #3

This question was expired because it remained in the 'Open' state without activity for the last 15 days.