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Systemic wins LIFT award, new version of Systemic (2.17)

I am very happy to announce that Systemic has been awarded the LIFT grant. This means that, together with my colleagues Joel Green and Randi Ludwig, I will be able to work full-time — instead of as a side project — on improving and expanding Systemic, and creating new educational apps like Systemic Live and Super Planet Crash, over the next year!

I am also releasing a new release of Systemic 2 (2.17) which addresses some bugs and improves the documentation for installation on Linux. You can download it now.

Below are some of the changes:

- NEW: ktable function for listing the fit values as a table, suitable for exporting to TeX or HTML
- NEW: Bayesian Information Criterion menu item
- NEW: Quadratic trend term
- CHANGED: Periodograms now report the normalized power in the manner of Zechmeister et al., 2009 (0 < p < 1, where power = 1 is a perfect fit).
- FIXED: bug where the semi-amplitude would be calculated incorrectly for massive bodies. (credit: Trifon Trifonov)
- FIXED: bug in simplex that would crash the application if the minimizer encountered a NaN value.
- FIXED: bug in the GUI that would crash the application in case of excessive text output.
- FIXED: Fixed naming of columns in the matrix returned by kdata().
- FIXED: bug where the radial velocity curve or periodogram would look excessively jagged.
- FIXED: bug in kperiodogram.boot where the function could crash.
- FIXED: bug in kperiodogram.boot where the function would only calculate the ‘full’ periodogram (instead of the periodogram of residuals) for certain inputs.
- FIXED: bug in the GUI periodogram routine, where you could receive an error for certain power spectra.
- FIXED: Kernel plot using plot() respects the chosen xlim.
- FIXED: MCMC would crash in certain situations when set up from the menu.
- FIXED: 1LO-crossval returns the signed sum of logs, instead of the absolute value.
- FIXED: clarified the installation instructions (Readme.txt) for Linux. (credit: Franz Feldtkeller)
- FIXED: you can now choose a path for R that is not /usr/bin/R by selecting Help -> Set path to R…
- FIXED: F-test menu item uses the current kernel instead of the kernel named “k”.
- Various bug-fixes in the plotting routines.

Bugs reported at https://github.com/stefano-meschiari/Systemic2/issues/2 are unfortunately still open due to lack of time to address them. They will be fixed in 2.18.

Funniest Software Bugs

This is a cute collection of fun software bugs from Michael Tsai’s blog: Funniest Software Bugs.

I incidentally enjoyed learning about the units shell command, a useful utility to convert between units from the command line:

stefano ~$ units
586 units, 56 prefixes
You have: 100 feet/s
You want: km/hr
	* 109.728
	/ 0.0091134442
You have: 30 J/yr
You want: erg/s
	* 9.5066294
	/ 0.10518975

(Its man page informs me that it cannot convert Celsius to Fahrenheit, since it can only handle multiplicative scale changes: boo!).  And what the heck is a fathom?