First Sunrise Images

After spending quite a bit of time moving to a new apartment (cleaning, packing, moving, more cleaning, and unpacking), I have had time to try using Patrik Jonsson’s Sunrise code.  The instructions on the Sunrise wiki were quite helpful. I ran into very few problems in the process. The biggest “problem” was a minor bug that took two minutes or so to figure out; the code requires the environment variable HOST to be defined. The code tries to handle the possibility that the name of the host computer is stored in the variable HOSTNAME (the default situation in Ubuntu), but there’s a problem with the implementation:

const char* h=getenv ("HOST");
if(h == 0)
  h = getenv ("HOSTNAME");
assert(h != 0);
string host (h);

First, h is declared as a const and initialized to the value stored in HOST. If this fails (i.e., if HOST is not defined), the code tries to set h to the value stored in HOSTNAME. Of course h is a constant, so it can’t take on any other value! I’ll see if the problem described in the previous post still exists. If it does, I’ll report both issues to Patrik on the Sunrise mailing list.

Here are the first few images that I generated using Sunrise. The images are only 300×300 pixels and the merger remnant isn’t centered properly, but it’s a start!

Now I need to play with parameters and learn more about manipulating the FITS files and analyzing spectra.


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