Editorial

Transcribed from the printed issue; not yet reviewed.

It has been a long time since were last able to print Vector, so here is a fat issue. It has been a busy time.

Ian Clark and his collaborators in the J community have published the second edition of At Play With J. Where the first edition carefully collected Eugene McDonnell’s Vector columns, the second edition revises all the examples for the J language as it is now, and so becomes an invaluable J textbook. Vector Books is proud to have published this.

Earlier this year Dyalog published Bernard Legrand‘s compendious Mastering Dyalog APL. At nearly 800 pages, generously illustrated, this is probably the best modern introduction to APL. This is a landmark publication that is doing much to make the language accessible to 21st-century programmers.

New faces appear, some of them drawn to Dyalog’s worldwide programming contest. This year we congratulate Ryan Tarpine, from Browns University in the US for winning the Grand Prize, which includes entry and travel to APL2010 in Berlin next month.

Eventually we lose others. We are sad to record the loss of Donald McIntyre and Eugene McDonnell, both long-standing contributors. Donald, writes Roger Hui, “was an eminent geologist who pioneered the use of of computers in geology. He was a gifted and inspiring teacher, an early and long-time APL and J user, and a friend and colleague of Ken Iverson.” Gene was “a family man, utterly decent, generous, kindhearted; also erudite and witty. His contributions to APL were graceful as well as useful.” (Larry Breed) Before his Vector columns, Gene wrote for APL Quote-Quad. “In my youth, when I was just starting in APL, on receiving an issue of the APL Quote-Quad I would inevitably and eagerly first turn to Eugene McDonnell’s ‘Recreational APL’ column. Through these columns I learned that it was possible for technical writing to be erudite, educational, and entertaining, and through them I learned a lot of APL.” (Roger Hui)

Catherine Lathwell is drawing attention with her documentary film project and its blog, Chasing The Men Who Stare At Arrays. Slobodan Blazeski put a spike in our website log with his article “Array languages for Lisp programmers”, which appears in this issue. Also in this issue, Graeme Robertson’s A Practical Introduction to APL, gets reviewed by a Stanford CompSci graduate student. Ajay Askoolum conducts a tour of Visual APL. Dan Baronet has more to tell about using Dyalog’s SALT for managing source code. We report meetings in Estonia and California.

Romilly Cocking reunites two old loves: APL and genetic algorithms. Simon Marsden calls on R for more power with statistics. Roger Hui shows that more performance can be wrung out of inner products, and that even the ‘unimprovable’ idiom for the arithmetic mean can be improved. Ray Polivka revisits the algorithm for finding Easter. An anonymous reader offers a problem of converting between representations to sharpen you up for writing .Net assemblies.

We start two new series. Howard Peelle uses J to play backgammon better. Jan Karman adds to the little published on K and q with a series Financial math in q.

Stephen Taylor