Seg fault when measuring time correlators

[tayral]

Hi,
I am studying the Hubbard dimer and willing to compute some correlator (e.g $ \langle N_\uparrow(\tau) N_\uparrow(\tau)\rangle$). Here is the script I am using:

from pytriqs.gf.local import *
from pytriqs.operators import *
from pytriqs.applications.impurity_solvers.cthyb_matrix import Solver
import pytriqs.utility.mpi as mpi

n_cycles=100000
V = 0.05
U = 5.0
mu = U/2.
beta = 100
e_h=0.5
alpha=0.5
split=0.0
t=1.

S = Solver(beta = beta, gf_struct = [ ('up',[1,2]), ('down', [1,2]) ])
for spin, g0 in S.G0 :
    g0[0,0] = iOmega_n + mu + split/2 - V**2 * (inverse(iOmega_n -e_h)  + inverse(iOmega_n + e_h))
    g0[1,0] = -t - alpha*V**2 *(inverse(iOmega_n -e_h)  + inverse(iOmega_n + e_h))
    g0[1,1] = iOmega_n + mu - split/2 - V**2 *(inverse(iOmega_n -e_h)  + inverse(iOmega_n + e_h))
    g0[0,1] = -t - alpha* V**2 *(inverse(iOmega_n -e_h)  + inverse(iOmega_n + e_h))
    g0.invert()

S.solve(H_local = U * (N('up',1) * N('down',1)+ N('up',2) * N('down',2)),   # Local Hamiltonian 
        quantum_numbers = {
          'Nup': N('up',1)+N('up',2),
          'Ndown': N('down',1)+N('down',2)
        },                   # Quantum Numbers 
        n_cycles  = n_cycles,                      # Number of QMC cycles
        length_cycle = 100,                      # Length of one cycle 
        n_warmup_cycles = 1000,                 # Warmup cycles
        n_legendre = 50,                         # Number of Legendre coefficients
        random_name = 'mt19937',                 # Name of the random number generator
        use_segment_picture = False,              # Use the segment picture
        measured_operators = {                   # Operators to be averaged
          'NimpA' : N('up',1)+N('down',1),
          'NimpB' : N('up',2)+N('down',2),
          },
        measured_time_correlators = {
           'Nup' : [N('up',1)+N('up',2),100]
        }
        )

This script runs fine when the last option of solve(), measured_time_correlators, is absent; when present, I get the error:

Starting on 1 Nodes at : 2014-05-25 14:10:13.513596
Hamiltonian with Eps0 term  : 
 5.0 C^(up,1)C(up,1)C^(down,1)C(down,1) + 5.0 C^(up,2)C(up,2)C^(down,2)C(down,2) - 2.5 C^(up,1)C(up,1) + C^(up,1)C(up,2) - C(up,1)C^(up,2) - 2.5 C^(up,2)C(up,2) - 2.5 C^(down,1)C(down,1) + C^(down,1)C(down,2) - C(down,1)C^(down,2) - 2.5 C^(down,2)C(down,2) 
Operator Nup already defined as Nup, using this instead for measuring
Inv Fourier done

[IPhT-IA-004525:04127] *** Process received signal ***
[IPhT-IA-004525:04127] Signal: Segmentation fault (11)
[IPhT-IA-004525:04127] Signal code:  (128)
[IPhT-IA-004525:04127] Failing at address: (nil)
[IPhT-IA-004525:04127] [ 0] /lib/x86_64-linux-gnu/libpthread.so.0(+0xfcb0) [0x7f1dac24fcb0]
[IPhT-IA-004525:04127] [ 1] /home/tayral/Work/TRIQS/install/lib/libcthyb_matrix_c.so(_ZN14Measure_OpCorr10accumulateESt7complexIdE+0x2ad) [0x7f1d9d18ec6d]
[IPhT-IA-004525:04127] [ 2] /home/tayral/Work/TRIQS/install/lib/libcthyb_matrix_c.so(_ZN5triqs8mc_tools10mc_genericISt7complexIdENS0_4Step10MetropolisIS3_EEE5startES3_RKSt8functionIFbvEE+0x273) [0x7f1d9d137483]
[IPhT-IA-004525:04127] [ 3] /home/tayral/Work/TRIQS/install/lib/libcthyb_matrix_c.so(_ZN5triqs3app16impurity_solvers9ctqmc_hyb5solveEv+0x71) [0x7f1d9d1333e1]
[IPhT-IA-004525:04127] [ 4] /home/tayral/Work/TRIQS/install/lib/python2.7/site-packages/pytriqs/applications/impurity_solvers/cthyb_matrix/cthyb_matrix.so(+0x33fb0) [0x7f1d9d404fb0]
[IPhT-IA-004525:04127] [ 5] /home/tayral/Work/TRIQS/install/lib/python2.7/site-packages/pytriqs/applications/impurity_solvers/cthyb_matrix/cthyb_matrix.so(+0x11747) [0x7f1d9d3e2747]
[IPhT-IA-004525:04127] [ 6] /home/tayral/Install/mypython/bin/python(PyObject_Call+0x36) [0x4e9f36]
[IPhT-IA-004525:04127] [ 7] /home/tayral/Install/mypython/bin/python(PyEval_EvalFrameEx+0x86a) [0x49846a]
[IPhT-IA-004525:04127] [ 8] /home/tayral/Install/mypython/bin/python(PyEval_EvalCodeEx+0x1a0) [0x49f1c0]
[IPhT-IA-004525:04127] [ 9] /home/tayral/Install/mypython/bin/python(PyRun_FileExFlags+0xe1) [0x4a9081]
[IPhT-IA-004525:04127] [10] /home/tayral/Install/mypython/bin/python(PyRun_SimpleFileExFlags+0x1d1) [0x4a9311]
[IPhT-IA-004525:04127] [11] /home/tayral/Install/mypython/bin/python(Py_Main+0x55d) [0x4aa8bd]
[IPhT-IA-004525:04127] [12] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7f1daaf4e76d]
[IPhT-IA-004525:04127] [13] /home/tayral/Install/mypython/bin/python() [0x41b9b1]
[IPhT-IA-004525:04127] *** End of error message ***
/home/tayral/Work/TRIQS/install/bin/pytriqs: line 4:  4127 Segmentation fault      (core dumped) /home/tayral/Install/mypython/bin/python $@

Do you know where this comes from?
Thanks!