from numpy import *
import pyqtgraph as pg

## Switch to using white background and black foreground
pg.setConfigOption('background', 'w')
pg.setConfigOption('foreground', 'k')
## Get DATA 
F=load('tEvol.npz') # $HOME, extention is .npz !
#### CREATE WINDOW
win=pg.GraphicsWindow(title="Measured variables")# <===
win.resize(600,600)# <===
####### FIRST PLOT ########
if len(F['x'])>1:
    N= len(F['x']) # the number of points
    ttl="file %s N=%d"%("test",N)
    p1=win.addPlot(title=ttl)   # <===  
    p1.plot(F['x'],pen=(0,0,0))# <===
########## SECOND PLOT  ####################
print(len(F['Q']))
if len(F['Q'])>1:
    N= len(F['Q']) # the number of points
    MP=F['Q']
    ttl="Network Membrane Potential"
    p4=win.addPlot(title=ttl) # <===
    p4.plot(MP,pen=(0,0,0)) # <===
    p4.setLabel('left','membrane potential',units='mV')# <===   
    p4.setLabel('bottom','time (msec)') # <===
    #### THIRD PLOT ####
    Tot=N/1000. # Total time in sec
    tp=range(N-1) # numerical time vector 
    ti=Tot/N # Time interval in msec 
    #t=ti*tp # physical time vector
    A=fft.rfft(MP)
    TauNq=(1/(2.*ti)) # frequency step
    f=TauNq*linspace(0,1,N/2)
    A[0]=0
    fft=abs(A[0:N/2])
    win.nextRow()# <=== 
    p5=win.addPlot(title="Fourier Spectrum")# <=== 
    p5.plot(f,fft,pen=(0,0,0))# <=== 
    p5.setLabel('bottom','frequency',units='Hz')# <===  
pg.QtGui.QApplication.exec_()# <===