Hello everybody, I currently experience some problem with arrows in polar plots.
Everything is fine, as long as the arrow does not cross the zero line. Here is an example from the matplotlib gallery (http://matplotlib.sourceforge.net/examples/pylab_examples/polar_demo.html), but with an arrow pointing at 45° outward. To create the arrow I just added the following line: arr = plt.arrow(45, 0.5, 0,1 , alpha = 0.5, width = 0.1, edgecolor = 'black', facecolor = 'green',lw = 2) You can find the complete source code at the end of the mail. If I want to point the arrow in zero direction, arr = plt.arrow(0, 0.5, 0,1 , alpha = 0.5, width = 0.1, edgecolor = 'black', facecolor = 'green',lw = 2) there is only the silhouette of an arrow visible, but nearly everthing seems to be green (as the arrow should be). For me it seems as there are some problems with the periodicity in polar plots. Does anyone have an idea or a workaround? Thank you very much in advance Marie-Therese --------------------------------------------------------------------------- Source code to reproduce the zero direction "arrow" import matplotlib import numpy as np from matplotlib.pyplot import figure, show, rc, grid # radar green, solid grid lines rc('grid', color='#316931', linewidth=1, linestyle='-') rc('xtick', labelsize=15) rc('ytick', labelsize=15) # force square figure and square axes looks better for polar, IMO width, height = matplotlib.rcParams['figure.figsize'] size = min(width, height) # make a square figure fig = figure(figsize=(size, size)) ax = fig.add_axes([0.1, 0.1, 0.8, 0.8], polar=True, axisbg='#d5de9c') r = np.arange(0, 3.0, 0.01) theta = 2*np.pi*r ax.plot(theta, r, color='#ee8d18', lw=3) ax.set_rmax(2.0) grid(True) ax.set_title("And there was much rejoicing!", fontsize=20) #This is the line I added: arr = plt.arrow(0, 0.5, 0,1 , alpha = 0.5, width = 0.1, edgecolor = 'black', facecolor = 'green',lw = 2) show() ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
