On 02/11/2012 10:53 PM, Alexa Villaume wrote: > (Sorry about not replying to list before. I usually have to be pretty > vigilant about not clicking "Reply-All") > > I made my figure a pdf and the transparency works fine. So thanks! Just > another quick question is it the Postscript language itself that doesn't > support transparency or the way mpl handles postscript files?
It is the language itself. Eric > > On Sat, Feb 11, 2012 at 10:48 AM, Eric Firing <efir...@hawaii.edu > <mailto:efir...@hawaii.edu>> wrote: > > On 02/11/2012 10:30 AM, Alexa Villaume wrote: > > Thanks for replying Eric. > > > (You're welcome. But please keep replies on the list when they are > potentially useful to others, as yours is.) > > > > Here is my minimal script - > > import matplotlib > > frompylab import* > > import numpy as np > > importos > > > metals=np.arange(-3.0, 1.1, 0.1) > > U=np.arange(-6.0, 0.25, 0.25) > > o3=np.zeros([25,41]) > > > plt.contourf(metals, U, o3, levels=[o3col-nsig*o3sig], alpha=0.20, > colors='blue') > > plt.savefig("CoutourPlot.ps") > > > The Postscript language does not support transparency, so > transparency is lost when you use the mpl postscript backend. The > way to work around this, if you really need to end up with a > postscript file, is to save the file as pdf, and then use a > converter program to render that as postscript. (It might be a > "print-to-file" or "save-as" option on your pdf display program, for > example. I don't know what is typically available on a Mac, but > Macs have long been pdf-friendly. In general, the need for ps files > has been diminishing. I almost never generate them any more.) > > Eric > > > > It plots fine except except there is no transparency in colors > of the > contour, it's like alpha is always set to 1.0 > > On Sat, Feb 11, 2012 at 8:23 AM, Eric Firing <efir...@hawaii.edu > <mailto:efir...@hawaii.edu> > <mailto:efir...@hawaii.edu <mailto:efir...@hawaii.edu>>> wrote: > > On 02/11/2012 07:40 AM, Alexa Villaume wrote: > > Hi All, > > > > I'm just getting started with matplotlib. I'm trying to make a > contour > > plot using contourf and have the different paths colored and semi > > transparent but the alpha keyword doesn't seem to do anything. I > googled > > around and found that other people have had this same problem > but I > > didn't find a solution. Here's what I'm doing - > > > > contourf(metals, U, o3, levels=[o3col-nsig*o3sig, > o3col+nsig*o3sig], > > alpha=0.20, colors='magenta') > > > > contourf(metals, U, o2, levels=[o2col-nsig*o2sig, > o2col+nsig*o2sig], > > alpha=0.20, colors='blue') > > > > contourf(metals, U, c3, levels=[c3col-nsig*c3sig, > c3col+nsig*c3sig], > > alpha=0.20, colors='green') > > > > > > To plot them all together. > > > > For reference my machine is running Mac OS X 10.6.8 and my > version of > > matplotlib is 1.2.x > > > > Thanks! > > Please provide a minimal but complete script that > illustrates the > problem; describe what it is in the output that does not > match your > expectations. e.g., > > import numpy as np > import matplotlib.pyplot as plt > z = np.arange(20).reshape(4,5) > plt.contourf(z, levels=[2,3], alpha=0.2, colors='magenta') > plt.savefig("testcontourf___alpha.png") > > which produces a pale magenta stripe, as expected, with mpl > from github > master. > > Eric > > ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
