def _read_pitors(self, f):
""" Read the Pi-Orbital Torsion parameters """
self.pitors_list = PiTorsionList()
# Eat the next 3 lines
f.readline()
f.readline()
f.readline()
line = f.readline()
for i in xrange(self.pointers['npitors']):
try:
int(line[0:6])
at1 = int(line[9:15]) - 1
at2 = int(line[15:21]) - 1
self.pitors_list.add(self.atom_list[at1], self.atom_list[at2],
line[40:50])
except ValueError:
raise TinkerAnaloutError('Error parsing pi-torsion term')
line = f.readline()
