Say I have two catalogs of points, each in two-dimensional space. For each object in a catalog, I want to find the nearest object(s) in the other catalog. I can do this by computing the distances between every single unique pairs of objects and find the ones within a search radius and possibly doing an additional sort.
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For a radial profile of $I(r)$, the enclosed flux within the radius $r$ is given by
\[ F(r) = \int_{0}^{2 \pi} d\phi \int_{0}^{r} dr r I(r, \phi) \ . \]
I’m only concerned about azimuthal symmetric cases, so $F(r) = 2\pi \int_{0}^{r} dr r I(r)$ .
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The installation procedure is confusing only if you are not using csh (I use Bash) and if g77 is not available. Otherwise you can simply follow the installation procedure outlined in the official documentation file (i.e., bc03/doc/bc03.ps.gz).
First, you definitely need csh and a FORTRAN compiler:
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(November 25, 2010) I screwed up SExtractor installation for no reason and in an attempt to fix it, I’ve found a few things. After wasting a few hours again, I think this installation note can work for most people who can actually build software from source… I think the usefulness of this note will be limited though, as a new release of SExtractor appears imminent.
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You must love the name, but what the software does is far from sultry; it’s a piece of geekware.
Anyways, I needed to edit files when I install HOTPANTS, photometric alignment utility by Andrew Becker. Here is my installation note before I forget.
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