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)

My starred reader articles

Just posting up a few papers I found interesting.

Peng Wang and Tom Abel's paper on outflow feedback in clusters
A somewhat less interesting follow-up to the previous

HARP mapping of the Serpens cloud core

Neal Evans' review of low mass star formation observations

the MNRAS paper on supermassive stars in the LMC

Identification of molecular clouds from the FCRAO OGS

First!

First post by me on my own BLDG! I should transition to this address eventually...

Testing trackbacks?

I just want to see if "trackbacks" work at all. I recently posted about histograms on google spreadsheets .

While I'm at it, might as well throw up a link to my google code site .

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.

IDL-to-Python

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

Ghostscript error?

I've been receiving the following error when attempting to compile (ps2pdf) my w5 outflows paper:

Error: /rangecheck in --get--
Operand stack:
   pdfmark   --dict:20/25(ro)(L)--   --nostringval--   50
Execution stack:
   %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--   false   1   %stopped_push   1878   1   3   %oparray_pop   1877   1   3   %oparray_pop   1861   1   3   %oparray_pop   1755   1   3   %oparray_pop   --nostringval--   %errorexec_pop   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   %finish_show   --nostringval--   --nostringval--   8   6   1   --nostringval--   (pdf_text_enum_t)   %op_show_continue   --nostringval--
Dictionary stack:
   --dict:1153/1684(ro)(G)--   --dict:0/20(G)--   --dict:71/200(L)--   --dict:125/300(L)--   --dict:44/200(L)--   --dict:138/224(L)--
Current allocation mode is local
Last OS error: 2
Current file position is 267478928
GPL Ghostscript 8.71: Unrecoverable error, exit code 1

I get the same error with Ghostscript 8.64, but on my laptop, using the fink version, it works. Similarly, there are errors with the postscript, so I'm led to believe it's an error in latex:

$ latex --version
pdfTeX 3.1415926-1.40.10-2.2 (TeX Live 2009)
kpathsea version 5.0.0
Copyright 2009 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
There is NO warranty.  Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Compiled with libpng 1.2.39; using libpng 1.2.39
Compiled with zlib 1.2.3; using zlib 1.2.3
Compiled with xpdf version 3.02pl3

No idea what the cause is but it's time to start documenting steps and looking for a workaround. Compiling on the lappy isn't a good option.