parameters: (self)
docstring: Propagates the momenta for half a time step.
docstring_summary: Propagates the momenta for half a time step.
docstring_tokens: Propagates the momenta for half a time step .
function: def pstep(self):
        """Propagates the momenta for half a time step."""
  
        dthalf = self.dt*0.5
        dthalf2 = dthalf**2
        dthalf3 = dthalf**3/3.0
  
        fc = np.sum(depstrip(self.forces.f),0)/float(self.beads.nbeads)
        m = depstrip(self.beads.m3)[0]
        pc = depstrip(self.beads.pc)
  
        self.p += dthalf*3.0*( self.cell.V* ( self.press - self.beads.nbeads*self.pext ) +
                  float(self.beads.nbeads)/self.mdof*np.dot(pc,pc/m) )
  
        self.beads.p += depstrip(self.forces.f)*dthalf
function_tokens: def pstep ( self ) : dthalf = self . dt * 0.5 dthalf2 = dthalf ** 2 dthalf3 = dthalf ** 3 / 3.0 fc = np . sum ( depstrip ( self . forces . f ) , 0 ) / float ( self . beads . nbeads ) m = depstrip ( self . beads . m3 ) [ 0 ] pc = depstrip ( self . beads . pc ) self . p += dthalf * 3.0 * ( self . cell . V * ( self . press - self . beads . nbeads * self . pext ) + float ( self . beads . nbeads ) / self . mdof * np . dot ( pc , pc / m ) ) self . beads . p += depstrip ( self . forces . f ) * dthalf