import numpy as np
import matplotlib.pylab as pl
from matplotlib import gridspec


def otplot1D(a,b,M,title=''):
    """ Plot matrix M  with the source and target 1D distribution """
    
    na=M.shape[0]
    nb=M.shape[1]
    
    gs = gridspec.GridSpec(3, 3)
    
    
    xa=np.arange(na)
    xb=np.arange(nb)
    
    
    ax1=pl.subplot(gs[0,1:])
    pl.plot(xb,b,'r',label='Target distribution')
    pl.yticks(())
    pl.title(title)
    
    #pl.axis('off')
    
    ax2=pl.subplot(gs[1:,0])
    pl.plot(a,xa,'b',label='Source distribution')
    pl.gca().invert_xaxis()
    pl.gca().invert_yaxis()
    pl.xticks(())
    #pl.ylim((0,n))
    #pl.axis('off')
    
    pl.subplot(gs[1:,1:],sharex=ax1,sharey=ax2)
    pl.imshow(M,interpolation='nearest')
    
    pl.xlim((0,nb))