[Matplotlib-users] problem with multiple axes

[mariusz s. <mar...@gm...>]

Hi,  I'm trying to get a plot with multiple axes on the righ, and it does
not work. Attached is the plot: the second axis (ax2) is not correctly
plotted. The code is below. What is wrong? Why the labels and ticks are
displayed on the left axis?

Many thanks for your suggestions,

Claude


 import numpy

import pylab

# function needed:

def make_patch_spines_invisible(ax):

ax.set_frame_on(True)

ax.patch.set_visible(False)

for sp in ax.spines.itervalues():

sp.set_visible(False)



# lists:

timeBLM=[]

sigBLM=[]


timeQPS=[]

sigQPS=[]



# file to open:

file = open("WSQT_PMdata.csv","r")


for line in file:

 tokens=line.split()

i=len(tokens)

timeBLM.append(float(tokens[0]))

sigBLM.append(float(tokens[1]))

if i==4:

timeQPS.append(float(tokens[2]))

sigQPS.append(float(tokens[3]))


file.close()


# convert lists to numpy arrays:

NtimeQPS = numpy.array(timeQPS)

NsigQPS = numpy.array(sigQPS)


NtimeBLM = numpy.array(timeBLM)

NsigBLM = numpy.array(sigBLM)



#now also QPS heaters:

timeHeaters=numpy.array([-0.56, 0, 0.003, 0.005, 0.01, 0.015, 0.02, 0.025])

sigHeaters=numpy.array([2.999,2.753,2.316,1.960,1.667,1.422,1.218,1.047])


# B data:
fig = pylab.figure(1,figsize=(8,6))

pylab.grid(True)

pylab.title("Wire scanner quech test data")

fig.autofmt_xdate()

fig.subplots_adjust(right=0.77)


ax1 = fig.add_subplot(111)

ax1.set_xlabel("time [s]",fontsize=15)

ax1.set_ylabel("BLM signal [Gy/s]",fontsize=15)

ax1.set_xlim([-0.1,0.027])

ax1.set_ylim([0.,3.]);
ax1.plot(NtimeBLM,NsigBLM,'black',label='BLM signal')


# Q signal axis:

ax2 = ax1.twinx()
ax2.set_ylabel("QPS voltage [V]",fontsize=15,color = 'red')

ax2.set_xlim([-0.1,0.027])

ax2.set_ylim([-0.01,0.3])

for tl2 in ax2.get_yticklabels():

tl2.set_color('red')

tl2.set_fontsize(15)

ax2.plot(NtimeQPS,NsigQPS,color='red',lw=2.5,label = 'QPS signal')



# Q heaters:

ax3 = ax2.twinx()

make_patch_spines_invisible(ax3)

ax3.spines["right"].set_position(("axes", 1.2))

ax3.spines["right"].set_visible(True)

ax3.set_ylabel("quench heaters", fontsize=15, color = 'green')

ax3.set_xlim([-0.1,0.03])

ax3.set_ylim([0.,5.])

ax3.set_color('green')

for tl in ax3.get_yticklabels():

tl.set_color('green')

tl.set_fontsize(15)

ax3.plot(timeHeaters,sigHeaters,color = 'green',lw=2.5,label = 'quench
heaters')


# check object ID

print 'idax1=',id(ax1)

print 'idax2=',id(ax2)

print 'idax3=',id(ax3)



handles1, labels1 = ax1.get_legend_handles_labels()

handles2, labels2 = ax2.get_legend_handles_labels()

handles3, labels3 = ax3.get_legend_handles_labels()
ax1.legend(handles1+handles2+handles3, labels1+labels2+labels3,loc
=(0.07,0.75),prop={'size':11}, shadow = False)

# show plot on the screen:

pylab.show()