Sunday, September 22, 2013

Blog moved!

This blog has moved!  It is now hosted at
http://keflavich.github.io/blog/

Wednesday, November 3, 2010

Repositories for observers

I should have posted these a while ago....
casaradio is a subversion repository for folks at The Center for Astrophysics and Space Astronomy at CU Boulder to post radio astronomy related codes. So far, emphasizes single dish (GBT, Arecibo), but will include EVLA, CARMA, and ALMA eventually.
aposoftware is a similar page, but is a mercurial repository and is meant to include instrument-specific software for the Apache Point Observatory 3.5m telescope. Right now includes a TUI script or two and the TSPEC and DIS IRAF-twodspec pipelines.

I'd be remiss to leave out the BGPS pipeline even though it's mentioned on the previous post.

Also, agpy is my personal code repository.

BGPS data paper published

Metalinking! The BGPS paper finally made it onto astro-ph today. It will be published in ApJS before the year's end.

Links to all of the published BGPS papers at the Bolocam Data Team website

And just because I want more linking, here they all are again:
The Bolocam Galactic Plane Survey I. Survey Description and Data Reduction arXiv
The Bolocam Galactic Plane Survey II. Catalog of the Image Data arXiv
The Bolocam Galactic Plane Survey III. Characterizing Physical Properties of Massive Star-Forming Regions in the Gemini OB1 Molecular Cloud arXiv
The Bolocam Galactic Plane Survey IV: λ = 1.1 and 0.35 mm Dust Continuum Emission in the Galactic Center Region

The same set of links is reproduced at the pipeline googlecode page.

Monday, August 16, 2010

Neat new things....

1. sptool is a quick way to compare standards to stellar spectra. Nice, I'd been looking for a tool like that.
2. GNU screen captions are useful especially when working in a screen-within-a-screen environment (who does that, really?)
3. finally got SPLAT to work... turns out I just hadn't reduced my damned data
4. kill -STOP and kill -CONT are really useful ways to pause programs that are sucking up resources if you want to resume them later. Haven't tried this on "real" code yet.

Friday, August 13, 2010

Filled step plots in matplotlib

It's not possible to do a simple filled step plot in matplotlib using default
commands. Workaround:


def steppify(arr,isX=False,interval=0):
    """
    Converts an array to double-length for step plotting
    """
    if isX and interval==0:
        interval = abs(arr[1]-arr[0]) / 2.0
        newarr = array(zip(arr-interval,arr+interval)).ravel()
        return newarr

plot(xx,yy,linestyle='steps-mid',color='b',linewidth=1.5)
fill_between(steppify(xx[x1:x2],isX=True),
    steppify(yy[x1:x2])*0,
    steppify(yy[x1:x2]),
    facecolor='b',alpha=0.2)

Wednesday, July 28, 2010

Histogram in Google Spreadsheet

It's not easy to make a histogram in google spreadsheets without replicating data. The "countif" function would be great, except it only allows very simple criteria. However, there's a workaround:
=count(Filter('Grades'!V2:V30,'Grades'!V2:V30>0.9))
=count(Filter('Grades'!V2:V30,'Grades'!V2:V30<0.9,'Grades'!V2:V30>0.8))

The Filter() function returns an array, which can be operated on like any other set of cells.

It's still not easy to make a nice-looking histogram, but the output of this process is at least usable.

Friday, July 9, 2010

IDL-to-Python

astrobetter started up an idl-to-python guide on their wiki.