importmatplotlib.pyplotaspltimportnumpyasnpfrommatplotlib.projectionsimportPolarAxesfrommatplotlib.transformsimportAffine2Dimportmpl_toolkits.axisartist.angle_helperasangle_helperimportmpl_toolkits.axisartist.floating_axesasfloating_axesfrommpl_toolkits.axisartist.grid_finderimportDictFormatter,FixedLocator,MaxNLocator# Fixing random state for reproducibilitynp.random.seed(19680801)defsetup_axes1(fig,rect):"""    A simple one.    """tr=Affine2D().scale(2,1).rotate_deg(30)grid_helper=floating_axes.GridHelperCurveLinear(tr,extremes=(-0.5,3.5,0,4),grid_locator1=MaxNLocator(nbins=4),grid_locator2=MaxNLocator(nbins=4))ax1=fig.add_subplot(rect,axes_class=floating_axes.FloatingAxes,grid_helper=grid_helper)ax1.grid()aux_ax=ax1.get_aux_axes(tr)returnax1,aux_axdefsetup_axes2(fig,rect):"""    With custom locator and formatter.    Note that the extreme values are swapped.    """tr=PolarAxes.PolarTransform()pi=np.piangle_ticks=[(0,r"$0$"),(.25*pi,r"$\frac{1}{4}\pi$"),(.5*pi,r"$\frac{1}{2}\pi$")]grid_locator1=FixedLocator([vforv,sinangle_ticks])tick_formatter1=DictFormatter(dict(angle_ticks))grid_locator2=MaxNLocator(2)grid_helper=floating_axes.GridHelperCurveLinear(tr,extremes=(.5*pi,0,2,1),grid_locator1=grid_locator1,grid_locator2=grid_locator2,tick_formatter1=tick_formatter1,tick_formatter2=None)ax1=fig.add_subplot(rect,axes_class=floating_axes.FloatingAxes,grid_helper=grid_helper)ax1.grid()# create a parasite Axes whose transData in RA, czaux_ax=ax1.get_aux_axes(tr)aux_ax.patch=ax1.patch# for aux_ax to have a clip path as in axax1.patch.zorder=0.9# but this has a side effect that the patch is# drawn twice, and possibly over some other# artists. So, we decrease the zorder a bit to# prevent this.returnax1,aux_axdefsetup_axes3(fig,rect):"""    Sometimes, things like axis_direction need to be adjusted.    """# rotate a bit for better orientationtr_rotate=Affine2D().translate(-95,0)# scale degree to radianstr_scale=Affine2D().scale(np.pi/180.,1.)tr=tr_rotate+tr_scale+PolarAxes.PolarTransform()grid_locator1=angle_helper.LocatorHMS(4)tick_formatter1=angle_helper.FormatterHMS()grid_locator2=MaxNLocator(3)# Specify theta limits in degreesra0,ra1=8.*15,14.*15# Specify radial limitscz0,cz1=0,14000grid_helper=floating_axes.GridHelperCurveLinear(tr,extremes=(ra0,ra1,cz0,cz1),grid_locator1=grid_locator1,grid_locator2=grid_locator2,tick_formatter1=tick_formatter1,tick_formatter2=None)ax1=fig.add_subplot(rect,axes_class=floating_axes.FloatingAxes,grid_helper=grid_helper)# adjust axisax1.axis["left"].set_axis_direction("bottom")ax1.axis["right"].set_axis_direction("top")ax1.axis["bottom"].set_visible(False)ax1.axis["top"].set_axis_direction("bottom")ax1.axis["top"].toggle(ticklabels=True,label=True)ax1.axis["top"].major_ticklabels.set_axis_direction("top")ax1.axis["top"].label.set_axis_direction("top")ax1.axis["left"].label.set_text(r"cz [km$^{-1}$]")ax1.axis["top"].label.set_text(r"$\alpha_{1950}$")ax1.grid()# create a parasite Axes whose transData in RA, czaux_ax=ax1.get_aux_axes(tr)aux_ax.patch=ax1.patch# for aux_ax to have a clip path as in axax1.patch.zorder=0.9# but this has a side effect that the patch is# drawn twice, and possibly over some other# artists. So, we decrease the zorder a bit to# prevent this.returnax1,aux_ax

fig=plt.figure(figsize=(8,4))fig.subplots_adjust(wspace=0.3,left=0.05,right=0.95)ax1,aux_ax1=setup_axes1(fig,131)aux_ax1.bar([0,1,2,3],[3,2,1,3])ax2,aux_ax2=setup_axes2(fig,132)theta=np.random.rand(10)*.5*np.piradius=np.random.rand(10)+1.aux_ax2.scatter(theta,radius)ax3,aux_ax3=setup_axes3(fig,133)theta=(8+np.random.rand(10)*(14-8))*15.# in degreesradius=np.random.rand(10)*14000.aux_ax3.scatter(theta,radius)plt.show()

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