Error when calculating repulsive interactions

[ludovica-beltrame]

When I try to run the pyinteraph analysis for repulsive interactions with this script:

#source the gromacs for pyinteraph analysis
modelID=$1
variant=$2
source /usr/local/gromacs-5.1.5/bin/GMXRC.bash
module load python/3.7
#have charged_group.ini
cp ../../../4.frames/pdbmovie_1.pdb reference.pdb
path=../../../../../../../../../../simulations/zinc_bound/$2/$1/CHARMM22star/md/Mol_An
gro=update.gro
traj=center_traj.xtc
pdb=reference.pdb
#pyinteraph analysis for repulsive interactions
#if you want to define other modes for the analysis: --sb-mode {different_charge,same_charge,all}
pyinteraph -s $pdb -t $path/$traj -r $pdb --sb-co 5 -b --sb-mode same_charge --sb-graph rep-graph.dat --ff-masses charmm27 -v --sb-cg-file charged_groups.ini

I get this error:

Traceback (most recent call last):
File "/usr/local/envs/py37/bin/pyinteraph", line 11, in
load_entry_point('pyinteraph==1.1', 'console_scripts', 'pyinteraph')()
File "/usr/local/envs/py37/lib/python3.7/site-packages/pyinteraph-1.1-py3.7-linux-x86_64.egg/pyinteraph/main.py", line 910, in main
cgs = cgs)
File "/usr/local/envs/py37/lib/python3.7/site-packages/pyinteraph-1.1-py3.7-linux-x86_64.egg/libinteract/libinteract.py", line 1334, in do_interact
correction_func = correction_func)
File "/usr/local/envs/py37/lib/python3.7/site-packages/pyinteraph-1.1-py3.7-linux-x86_64.egg/libinteract/libinteract.py", line 638, in calc_dist_matrix
sets_sizes[s_index][0]))
File "libinteract/innerloops.pyx", line 81, in libinteract.innerloops.LoopDistances.run_triangular_mindist
File "<array_function internals>", line 6, in sum
File "/usr/local/envs/py37/lib/python3.7/site-packages/numpy/core/fromnumeric.py", line 2260, in sum
initial=initial, where=where)
File "/usr/local/envs/py37/lib/python3.7/site-packages/numpy/core/fromnumeric.py", line 86, in _wrapreduction
return ufunc.reduce(obj, axis, dtype, out, **passkwargs)
TypeError: cannot perform reduce with flexible type

@elenapapaleo @mtiberti @ValeSora can anyone of you help me in solving this issue please?