06 December 2012

Announcing the ESIO library

I've just publicly released a scientific library called ESIO used to generate the results I've recently presented.  ESIO has been used broadly within my research group and I consider it production-ready. 

ESIO simplifies getting high throughput input and output of structured data sets using parallel HDF5. The library is written in C99 and may be used by C89 or C++ applications. A Fortran API built atop the F2003 standard ISO_C_BINDING is also available.  ESIO is LGPL software and is available from https://red.ices.utexas.edu/projects/esio/wiki.

In particular, ESIO provides:

  • Distributed IO of 1D lines, 2D planes, and 3D fields of data
  • Support for scalar-, complex-, and vector-valued data
  • Single and double precision floating point storage
  • A mechanism for storing both string and numeric metadata
  • Support for contiguous and strided in-memory data
  • Support to simplify writing restart file sequences
  • A handy esio_bench utility for performance benchmarking
  • A comprehensive regression suite
I am long, long overdue on creating a paper introducing ESIO.

APS DFD 2012 Talk Slides

Here are the slides from the talk I gave at APS DFD 2012 just before Thanksgiving:
Turbulence statistics with quantified uncertainty in cold-wall supersonic channel flow

15 July 2012

Generating the Thorn fractal in binary PGM format

While looking to test a Burg recursion implementation I'd written, I stumbled across some AR(p) test cases by Paul Bourke.  I emailed him to ask a question and, while browsing for his address, I stumbled across his material on the Thorn Fractal.  His (9.984, 7.55) image really struck me so I downloaded Paul's sample code.  Alas, it produced output in some "raw" image format that I couldn't coax ImageMagick or The GIMP into reading.  After digging around a bit, I decided to roll my own code to dump the output in binary PGM so that nearly any tool can postprocess the data.

Tada.  A grayscale version of (9.984, 7.55) created at 10000x10000, cropped, and downsampled to 1600x900 suitable for background use:

While most of the code was a one-off, I could see the PGM bits being useful again.  Feedback from anyone who knows 16-bit grayscale details well much appreciated the Thorn fractal needs nothing like 16-bits of information.  Incidentally, one could save a factor of two on the memory by using uint8_t instead of uint16_t.

24 May 2012

P-Value Extravaganza

A ridiculous (and informative) final project by the very talented Jesse Kelly for Bill Press' statistics course:

23 May 2012

Sleeping Bag by Jordan Moser

Our friend Jordan released his first album a few weeks back. My wife Michelle has used his work in her choreography. We're both huge fans. Jordan's music is great for a crowded bar or a quiet evening. His lyrics are nothing short of excellent. For $7 you can go pick up a copy. The words in his song The Curtains quite literally always give me chills:

She calls it walking out
but that's not what it's about.
We don't see eye to eye
and there's no tellin' why.
She don't say nothing now.
She's got her shit all figured out.
The real matter is
who's gonna keep the curtains?

Barry was eighty-five.
Kathy, his lovin' wife,
never thought in a million years
she would be standing here,
calling the funeral home,
going to bed alone.
She's gotta face all the relatives.
He left her with the curtains.

Don't know if love's a gift
or just something that someone did
and couldn't stop talking about
until none could do without.
The smell of the open air
as it drifts through your lover's hair...
Doesn't every love come to this?
Who's gonna keep the curtains?

The dust underneath the bed,
the terrible things she said
like "give me my money back"
prepare for the final act.
And when the big red curtains close
she turns to the life she chose.
But I didn't ask for this.
Who's gonna keep the curtains?

The Curtains by Jordan Moser from his album Sleeping Bag
Released 3 May 2012 by Albino Crow Music
Available from http://albinocrowmusic.bandcamp.com/album/sleeping-bag
Lyrics by Jordan Moser. All rights reserved.

08 January 2012


Two years after our friend Nancy snagged the domain, we finally put up some content at http://michellethompson.org/...

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