Archive for October, 2011

Tuesday, October 18th, 2011

Modern IDL 1.1 update

I’ve updated Modern IDL for some of the IDL 8.1 features, notably GRIB, function graphics enhancements1, and the IDLffVideoWrite class. PDF purchasers from this point on should get the new version and I will send out the update to the purchasers of the old PDF shortly. The first run of the print book is all […]

1 Comment » - Posted in Books,IDL by

Wednesday, October 12th, 2011

Set operations on non-negative integers

Arrays of non-negative integers are encountered frequently in IDL, e.g., for index arrays and lists of ENVI file IDs to name a couple examples. Since valid data elements are non-negative integers, -1 is used to indicate an empty set. I have a few routines for efficiently computing set unions, intersections, differences, and complements. For example, […]

No Comments » - Posted in IDL,Optimization by

Tuesday, October 11th, 2011

Combining testing methods

Finding severe bugs after a release is 100 more expensive than before (2x for non-critical bugs), so how can more bugs be found before release? This article suggests combining multiple testing/review methods, particularly adding code review: More generally, inspections are a cheaper method of finding bugs than testing; according to Basili and Selby (1987), code […]

No Comments » - Posted in mgunit by