I was wondering, is it possible to offset the start of the radial axis or move it outside of the graph.
This is what I'm hoping to achieve:
And this is what I have for now.
I have read the documentation and different topics on SO, but I couldn't find anything helpful. Does that mean that it is not even possible if it is not mentioned anywhere.
Thank you in advance.
EDIT (added snippet of a code used to create the plot):
ax = fig.add_subplot(111, projection='polar') ax.set_theta_zero_location('N') ax.set_theta_direction(-1) ax.plot(X,lines[li]*yScalingFactor,label=linelabels[li],color=color,linestyle=ls)
I am not sure if the polar plot can be adjusted like that. But here is a work-around, based on the last example given here: Floating Axes.
I have included explanatory comments in the code, if you copy/paste it, it should run as-is:
import mpl_toolkits.axisartist.floating_axes as floating_axes from matplotlib.projections import PolarAxes from mpl_toolkits.axisartist.grid_finder import FixedLocator, \ MaxNLocator, DictFormatter import numpy as np import matplotlib.pyplot as plt # generate 100 random data points # order the theta coordinates # theta between 0 and 2*pi theta = np.random.rand(100)*2.*np.pi theta = np.sort(theta) # "radius" between 0 and a max value of 40,000 # as roughly in your example # normalize the r coordinates and offset by 1 (will be clear later) MAX_R = 40000. radius = np.random.rand(100)*MAX_R radius = radius/np.max(radius) + 1. # initialize figure: fig = plt.figure() # set up polar axis tr = PolarAxes.PolarTransform() # define angle ticks around the circumference: angle_ticks = [(0, r"$0$"), (.25*np.pi, r"$\frac{1}{4}\pi$"), (.5*np.pi, r"$\frac{1}{2}\pi$"), (.75*np.pi, r"$\frac{3}{4}\pi$"), (1.*np.pi, r"$\pi$"), (1.25*np.pi, r"$\frac{5}{4}\pi$"), (1.5*np.pi, r"$\frac{3}{2}\pi$"), (1.75*np.pi, r"$\frac{7}{4}\pi$")] # set up ticks and spacing around the circle grid_locator1 = FixedLocator([v for v, s in angle_ticks]) tick_formatter1 = DictFormatter(dict(angle_ticks)) # set up grid spacing along the 'radius' radius_ticks = [(1., '0.0'), (1.5, '%i' % (MAX_R/2.)), (2.0, '%i' % (MAX_R))] grid_locator2 = FixedLocator([v for v, s in radius_ticks]) tick_formatter2 = DictFormatter(dict(radius_ticks)) # set up axis: # tr: the polar axis setup # extremes: theta max, theta min, r max, r min # the grid for the theta axis # the grid for the r axis # the tick formatting for the theta axis # the tick formatting for the r axis grid_helper = floating_axes.GridHelperCurveLinear(tr, extremes=(2.*np.pi, 0, 2, 1), grid_locator1=grid_locator1, grid_locator2=grid_locator2, tick_formatter1=tick_formatter1, tick_formatter2=tick_formatter2) ax1 = floating_axes.FloatingSubplot(fig, 111, grid_helper=grid_helper) fig.add_subplot(ax1) # create a parasite axes whose transData in RA, cz aux_ax = ax1.get_aux_axes(tr) aux_ax.patch = ax1.patch # for aux_ax to have a clip path as in ax ax1.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. # plot your data: aux_ax.plot(theta, radius) plt.show()
This will generate the following plot:
You'd have to tweak the axis labels to meet your demands.
I scaled the data because otherwise the same issue as with your plot would have occurred - the inner, empty circle would have been scaled to a dot. You might try the scaling with your polar plot and just put custom labels on the radial axis to achieve a similar effect.
