Merge lp:~maddevelopers/mg5amcnlo/MadSpin_correctbug into lp:mg5amcnlo/lts

[Pierre Artoisenet]

Hi Olivier,

This is the correction to the bug

https://bugs.launchpad.net/bugs/1378925

For some reason the status of the random generator was not properly
written down before each termination of the fortran code in the unweighting mode.

I have checked that the ranmar state is properly written down in this version.
Following Markus suggestion, I also set the max number of calculators to a low number
and check the absence of spikes in the distributions (for pp > tt~ j, all decay channels)

Cheers,
Pierre

[lp:~maddevelopers/mg5amcnlo/MadSpin_correctbug]

258. By <email address hidden> on 2014-10-16

small correction

[Olivier Mattelaer (olivier-mattelaer)]

Hi Pierre,

I agree that your fix is working, but I think that we need to slightly secure it for the random seed problem in the future.

So here is my suggestions:
1) add an check that the routine "calculate_matrix_element"
is only use in mode "decay"
i.e.
replace the lines:
        if mode == 'prod':
            info = int(external.stdout.readline())
            nb_output = abs(info)+1
        else:
            info = 1
            nb_output = 1
by
        if mode != 'prod':
            raise Exception, "Mode not supported anymore in this function (not save for seed)"
        info = 1
        nb_output = 1
2) having a nice treatment of that part as well.

This is of course very small but will make me sleep better ;-)

Cheers,

Olivier

review: Needs Fixing

=== modified file 'MadSpin/decay.py'
--- MadSpin/decay.py	2014-09-17 09:53:23 +0000
+++ MadSpin/decay.py	2014-10-16 13:08:38 +0000
@@ -3221,14 +3221,23 @@
             helicities=[lastline[i] for i in range(len(lastline))]
             output = trials, BWvalue, weight, momenta, failed, use_mc_masses, helicities
 
-        if len(self.calculator) > 100:
-            logger.debug('more than 100 calculator. Perform cleaning')
+        if len(self.calculator) > self.options['max_running_process']:
+            logger.debug('more than %s calculators. Perform cleaning' % self.options['max_running_process'])
             nb_calls = self.calculator_nbcall.values()
             nb_calls.sort()
             cut = max([nb_calls[len(nb_calls)//2], 0.001 * nb_calls[-1]])
             for key, external in list(self.calculator.items()):
                 nb = self.calculator_nbcall[key]
                 if nb < cut:
+                    if key[0]=='full':
+                      path=key[1]
+                      end_signal="5 0 0 0 \n"  # before closing, write down the seed 
+                      external.stdin.write(end_signal)
+                      ranmar_state=external.stdout.readline()
+                      ranmar_file=pjoin(path,'ranmar_state.dat')
+                      ranmar=open(ranmar_file, 'w')
+                      ranmar.write(ranmar_state)
+                      ranmar.close()
                     external.stdin.close()
                     external.stdout.close()
                     external.terminate()