Alexandar Hansen wrote: > Hello, > > I've been struggling with this for a while now and have effectively > two issues. One, how can I define the range over which hexbin ... > bins? And two, how do I change the background color of a plot?
Alexandar: To change the background color to the lowest value in the colormap: ax = plt.gca() ax.set_axis_bgcolor(plt.cm.jet(0)) -Jeff > The latter I thought would be trivial, but nothing I've tried has > worked. Let's take the example: > > import numpy as np > import matplotlib.cm <http://matplotlib.cm> as cm > import matplotlib.pyplot as plt > > n = 100000 > x = np.random.standard_normal(n) > y = 2.0 + 3.0 * x + 4.0 * np.random.standard_normal(n) > #xmin = x.min() > #xmax = x.max() > #ymin = y.min() > #ymax = y.max() > xmin = 0 > xmax = 10 > ymin = 0 > ymax = 30 > > plt.hexbin(x,y, cmap=cm.jet) > #plt.hexbin(x,y, cmap=cm.jet, extent=[xmin, xmax, ymin, ymax]) > plt.axis([xmin, xmax, ymin, ymax]) > plt.title("Hexagon binning") > cb = plt.colorbar() > cb.set_label('counts') > > plt.show() > > > Let's say i'm only interested in the positive quadrant of the data, so > I only want to bin data in the range of 0-10 in x and 0-30 in y. The > first thing I tried was to use the extent option to only bin the > specified range of data, but that gives these errors: > > [tesla:~/NMR/500-Tupp/IM7][349] HexBin.py > Traceback (most recent call last): > File "HexBin.py", line 28, in <module> > plt.hexbin(x,y, cmap=cm.jet, extent=[xmin, xmax, ymin, ymax]) > File "/usr/lib64/python2.5/site-packages/matplotlib/pyplot.py", line > 1920, in hexbin > ret = gca().hexbin(*args, **kwargs) > File "/usr/lib64/python2.5/site-packages/matplotlib/axes.py", line > 5447, in hexbin > collection.update(kwargs) > File "/usr/lib64/python2.5/site-packages/matplotlib/artist.py", line > 548, in update > raise AttributeError('Unknown property %s'%k) > AttributeError: Unknown property extent > > > After that, I just set the plt.axis range to what I'm interested in. > However, the range not binned by hexbin shows up as white, instead of > the 0-count blue. I've tried adding facecolor, edgecolor, axisbg, and > who knows what else as part of plt.hexbin, plt.axis, and plt.savefig, > But most have no consequence on the plot. plt.savefig(myname, > facecolor='blue') successfully changed everything blue except the > white region within the plot. > > So, where am I going wrong? I'm finding myself out of options and > would ideally not like to trim or add false points to my data just to > get the axis and colors correct. > > Best, > Alex > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------------ > > ------------------------------------------------------------------------ > > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > ------------------------------------------------------------------------------ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
