Mailman 3 March 2011 - yt-users

bitbucket success story
by j s oishi March 10, 2011

March 10, 2011

Hi All, I know there have been some big changes for users of yt recently: yt-2.0 and the move to BitBucket for repository hosting. I just wanted to tell you a bit about what the latter has given us. Recently, Andrew Myers, a yt user from the Orion group at Berkeley, contacted us about some patches he'd made to support the forthcoming Orion2 code, which is based on Chombo. Matt and I had written a bare-bones Chombo reader quite some time ago, in a rush. As I recall, it was written between … [View More]

1 0

Colorbar values
by Sam Skillman March 9, 2011

March 9, 2011

Hi all, I was wondering if anyone has recently experienced issues with the colorbar values not showing up on logarithmic data in slices and projections. I upgraded my matplotlib within the last week or two and they seemed to have disappeared, and reverting to older installs doesn't seem to be helping. I believe this is an issue with my custom 64-bit install on OS X but if anyone has any thoughts I'm all ears. Thanks, Sam

2 3

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 9, 2011

March 9, 2011

Geoffrey, > This is what I get for a density threshold of zero, and I think that it > isn't a problem. When you set your density limit to zero, every pair of > points in the volume will satisfy the pair matching condition, and you're > really not measuring anything interesting. I've thought a bit more about this, and I want to be clearer with my explanation. Remember that \xi is the "surplus" probability that you're measuring over a Gaussian random field of densities. If you … [View More]

1 0

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 9, 2011

March 9, 2011

Geoffrey, > One is that I'm getting 0 correlation on all length scales... which is > bad. I've set the min density threshold to 0 and played around with other > parameters but still get 0 for the \xi column in the output > dens_tpcorr_correlation.txt. Can you check this on a small dataset to see > if that's what you get, or I am doing something terribly wrong. (do I > have to re-Cython or missed some other things?) This is what I get for a density threshold of zero, and … [View More]

1 0

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 9, 2011

March 9, 2011

Geoffrey, > from yt.mods import * > from yt.utilities.kdtree import * > amods.two_point_functions.TwoPointFunctions What Matt meant is that you have the option of doing something like this: from yt.mods import * tpf = amods.two_point_functions.TwoPointFunctions(pf, ....) Or something like this: from yt.mods import * from yt.analysis_modules.two_point_functions.api import * tpf = TwoPointFunctions(pf, .....) I apologize that the examples in the documentation have not been updated … [View More]

2 1

Re: [yt-users] timing parallel runs
by Stephen Skory March 9, 2011

March 9, 2011

Hi Dave, > Now that I think of it timing slices man not be the ideal thing to test. I will > have a look at your pointers. How is the in-situ work on enzo going. Is there a > section in the YT docs that deals with using YT in this fashion? I have some inside knowledge that Matt is mostly incommunicado for the next couple days, so I'll field your question. You should look at the enzo documentation, here, for some information on inline analysis. http://docs.enzo.googlecode.com/hg/… [View More]

2 1

timing parallel runs
by Dave Semeraro March 8, 2011

March 8, 2011

Hi there, I am trying to get a feel for how YT scales in parallel. I am using the time() function of python to wrap individual parts of a yt script. For example, I do this: start = time.time() pc.add_slice("Density", 0) end = time.time() slicetime = end - start print "slice took %f seconds" %slicetime Each rank does this and I get a variety of times across ranks. I am not seeing any difference in the max time with number of processes however. For example, if the max across ranks for the … [View More]

2 2

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 8, 2011

March 8, 2011

Geoffrey, I've just added the modification to the 'yt' branch. Update and you should have it. I've added these two parameters to the TwoPointFunctions() class: theta : Float For random pairs of points, the second point is found by traversing a distance along a ray set by the angle (theta, phi) from the first point. To keep this angle constant, set ``theta`` to a value in the range [0, 2pi). Default = None, which will randomize theta for every pair of points. phi : Float … [View More]

3 3

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 8, 2011

March 8, 2011

> I just want to confirm if the coordinates are implemented differently in > YT. In the usual spherical coordinates for physicists, (r, theta, phi), > theta is defined from the azimuthal (from the z axis), and phi is in the > (x,y) plane. So shouldn't phi go from 0 to 2pi, and theta go from 0 to > pi? You're right, Geoffrey. I've switched the two and fixed the range, and the changes have been pushed. Thanks for pointing that out. Stephen Skory stephenskory(a)yahoo.com http:… [View More]

1 0

Re: [yt-users] 1D matter power spectrum
by Stephen Skory March 7, 2011

March 7, 2011

Geoffrey, > is there a way to limit the random total_values of pts generated for say > (r, theta, phi) in the physics convention? > > x = (phi = 0, theta = pi/2) > y = (phi = pi/2, theta = pi/2) > z = (phi = *, theta = 0) I am sorry, but I don't understand what you mean. "total_values" is just the absolute number of point pairs generated. Are you referring to the range of x,y,z values generated for points? If so, I still don't understand what you mean with phis and thetas.… [View More]

3 4