#!/usr/bin/env python

#
# $Id: vort.py,v 1.1 2009/09/22 10:12:58 dintrans Exp $
# Animate the vorticity snapshots with the velocity field superimposed
#

import numpy as N
import pylab as P
import pencil as pc

vort, t = pc.read_slices(field='oo2', proc=0)
ux, t = pc.read_slices(field='uu1', proc=0)
uz, t = pc.read_slices(field='uu3', proc=0)

dim=pc.read_dim()
par=pc.read_param(quiet=True)
par2=pc.read_param(quiet=True, param2=True)
grid=pc.read_grid(param=par, quiet=True, trim=True)
nt=len(t)
vort=vort.reshape(nt, dim.nz, dim.nx)
ux=ux.reshape(nt, dim.nz, dim.nx)
uz=uz.reshape(nt, dim.nz, dim.nx)

qs1=N.random.random_integers(0,dim.nx-1, 1000)
qs2=N.random.random_integers(0,dim.nz-1, 1000)
xx,zz=P.meshgrid(grid.x, grid.z)
frame=par.xyz0[0],par.xyz1[0],par.xyz0[2],par.xyz1[2]

P.ion()
im=P.imshow(vort[nt-1,...], extent=frame, origin='lower', aspect='auto')
a=ux[nt-1, qs2, qs1]**2+uz[nt-1, qs2, qs1]**2 ; norm=N.sqrt(a.max())
ux[nt-1, qs2, qs1]=ux[nt-1, qs2, qs1]/norm
uz[nt-1, qs2, qs1]=uz[nt-1, qs2, qs1]/norm
vel=P.quiver(xx[qs2, qs1], zz[qs2, qs1], ux[nt-1, qs2, qs1],
uz[nt-1, qs2, qs1], scale=7)
st=P.figtext(0.8,0.2,'t=%.1f'%t[0], color='w')
P.xlabel('x')
P.ylabel('z')

P.show()