LabVIEW User Group Meeting March 18 2014 Cole Van Vlack

Outline LVUG Motivation Configuration Files Sharpening the Saw The Compounding Effect Configuration Files

Sharpening the Saw

Why is this important? If the below numbers kept showing up in every experiment you performed or in the results section of every academic paper you read, what would you do? 360,000—the number of people with graduate degrees on government assistance in 2010 68,000—number of postdocs in the U.S. alone waiting for tenured professorships 100,000—number of PhDs granted in a four year period 16,000—number of professorships opened in the same four year period 84,000—number of PhDs left over every four years >60%—number of PhDs who will NOT have a paying job at graduation <1%—number PhDs will go on to be tenured professors. Less than 1%! 43%—PhD students will NOT get their PhD within 10 years of starting graduate school $42,000 (or ~$19/hour)—annual starting salary (before taxes) of a postdoc in the U.S. $55,272 (or ~$26/hour)—salary of a 7th year postdoc. $56,370—salary of an average librarian http://cheekyscientist.com/leave-academia/

Anecdote Queen’s Eng. Phys. Grad – 06 -> Top 5 Student Finished Master’s at Queen’s 08 PhD at Cambridge Post-Doc at MIT… Found there were two open faculty positions in Canada in physics departments in 2013.

Initial Topics Version Control Provenance Testing Configuration Files

Constants Please… no… Fine for math that doesn’t change (e.g. pi/2). If you don’t want it as a parameter, better to do this:

Controls W/ Defaults

Controls W/ Defaults Pros Cons Allows lots of parameters, but you don’t have to remember them all. Will be dumped to files if we use our provenance concepts w/ saving. Can Change them. Cons Other users can reset them. Can’t keep a complete “dataset” for a particular experiment.

Structured Configuration Files XML Used by lots of languages so should be easy to find a parser. Not Human readable. Easier to implement in LabVIEW. Adding variables to your code invalidates previous configuration files. Mention plain text files.

Structured Configuration Files INI Used by lots of languages so should be easy to find a parser. Human readable. Requires more work that XML, but isn’t crazy. Returns a “Found?” boolean so you can catch when values aren’t there and set them to defaults. Mention plain text files.

Graphical User Interface (GUI) Not much difference from main LabVIEW front panel. Makes the interface cleaner to have buttons that open GUIs rather than parameters everywhere. Can force the user to input parameters when something happens.

Dynamically Loaded Code Modules t_quench = 300.0 t_excite = 4.0 * t_quench / 5.0 if t_excite < 500.0: alpha = 0.0 beta = 1.0 else: alpha = 0.2 beta = 0.8 Note: Can be done in Python, but not LabVIEW. Just including for completeness. http://software-carpentry.org/v4/essays/config.html