def read_pmd(self,fname='pmd0000'):
f=open(fname,'r')
# 1st: lattice constant
self.alc= float(f.readline().split()[0])
# 2nd-4th: cell vectors
# for i in range(3):
# data= f.readline().split()
# self.a1[i]= float(data[0])
# self.a2[i]= float(data[1])
# self.a3[i]= float(data[2])
self.a1= np.array([float(x) for x in f.readline().split()])
self.a2= np.array([float(x) for x in f.readline().split()])
self.a3= np.array([float(x) for x in f.readline().split()])
# 5th-7th: velocity of cell vectors
tmp= f.readline().split()
tmp= f.readline().split()
tmp= f.readline().split()
# 8st: num of atoms
natm= int(f.readline().split()[0])
# 9th-: atom positions
self.atoms= []
symbol = None
for i in range(natm):
data= [float(x) for x in f.readline().split()]
ai= Atom()
ai.decode_tag(data[0])
if self.specorder:
symbol = self.specorder[ai.sid-1]
if symbol and ai.symbol != symbol:
ai.set_symbol(symbol)
ai.set_pos(data[1],data[2],data[3]) # position
ai.set_vel(data[4],data[5],data[6]) # velocity
ai.set_ekin(data[7])
ai.set_epot(data[8])
ai.set_strs(data[9],data[10],data[11],
data[12],data[13],data[14])
self.atoms.append(ai)
f.close()