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The Dyalog Blog

267 blog posts in 34 categories covering APL insights, company news and events, innovative projects, and more.

The most obvious expression for computing π in APL is ○1. But what if you can’t remember how ○ works, or your O key is broken, or you feel like… Read
Roger’s post speculating on Ken Iverson’s favourite APL expression reminded me that one of the delegates at Dyalog ’14 conducted a quick… Read
Quicksort is a classic sorting algorithm invented by C.A.R. Hoare in 1961 [0, 1]. It has been known for some time that quicksort has a terse rendition in APL… Read
What was Ken Iverson’s favourite APL expression? I don’t know that he had one and if he had I don’t know what it was, but if I have to guess …… Read
In one man’s humble opinion, reduction (⌿) is the Queen of Operators. Each (¨) comes a close second, but doesn’t get the cigar because each can… Read
Logo of the APL Problem Solving Competition, showing a stylised grey brain-shaped maze with a circular target symbol on the left hemisphere.
The winners of the 2014 APL Problem Solving Competition were recognized at the Dyalog ’14 user meeting and had a chance to share their competition… Read
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