[yt-users] change in add_projection/add_thin_projection for unweighted projections?

Matthew Turk matthewturk at gmail.com
Mon Aug 15 05:58:26 PDT 2011


Hi Christine,

The behavior should be the same; for weighted:

v = sum( f(i) * w(i) * dl(i) ) / sum( w(i) * dl(i) )

For unweighted:

v = sum( f(i) * dl(i) )

Looking over the code, it looks like your assessment is correct; the
weighting is taken and performed correctly, but the dls are not
converted into cm or the otherwise appropriate unit.  I have just
pushed out a fix in hash 3becbdffbc30; please test it and let me know
if it works for you.

Thanks very much for bringing this to my attention,

Matt

On Mon, Aug 15, 2011 at 12:21 AM, Christine Simpson
<csimpson at astro.columbia.edu> wrote:
> Hi all,
>
> Has there been a change to the add_projection or add_thin_projection routines for unweighted projections?  I have some projection scripts from ~a month ago that are all off by like 20 orders of magnitude on the color bar limits for unweighted projections.  The only thing that makes sense to me is that yt is now dividing the line of sight integration by the depth of the projection.  So it is sum(f(i)*dl(i))/sum(dl(i)) instead of sum(f(i)*dl(i)).  Is that right?  I don't think it used to do that.  It's fine if that is now what it is doing, but I just want to make sure.  I'm a little confused.
>
> Christine
> _______________________________________________
> yt-users mailing list
> yt-users at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>



More information about the yt-users mailing list