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Enhanced Debugging with Function Keys – Evaluate selection

See also Enhanced Debugging with Function Keys. When tracing through a complex dfn and reaching a guard (condition:result), I am often wary of tracing into… Read

Towards Improvements to Stencil

Background The stencil operator ⌺ was introduced in Dyalog version 16.0 in 2017. Recently we received some feedback (OK, complaints) that (a) stencil does… Read

Enhanced Debugging with Function Keys

Sometimes I want an additional functionality in the IDE. (Are you a RIDE user? We’ll cover that too!) For example, the other day, I was tracing through… Read

I-Beam Mnemonics

I-Beam (⌶) is an operator that takes as its operand a numeric code and derives a function which isn’t really considered to be part of the APL language… Read

Loops, Folds and Tuples

For-loops Given an initial state defined by a number of variables, a for-loop iterates through its argument array modifying the state.     A←... ⋄… Read

Quicksort in APL Revisited

A message in the Forum inquired on sorting strings in APL with a custom comparison function. First, sorting strings without a custom comparison function… Read

Zero-length Regular Expression Matches Considered Harmful

I was asked by a colleague why ⎕S reports two matches in the following example: ('d*'⎕S 0 1)'321' ┌───┬───┐ │0 3│3 0│… Read

Three-and-a-bit

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
Logo of the APL Problem Solving Competition, showing a stylised grey brain-shaped maze with a circular target symbol on the left hemisphere.

Solving the 2014 APL Problem Solving Competition – it’s as easy as 1 1 2 3…

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

A Speed-Up Story

The first e-mail of the work week came from Nicolas Delcros. He wondered whether anything clever can be done with ∘.≡ on enclosed character strings. I… Read

Creating Shortcuts (Microsoft Windows)

At Dyalog, a developer not only needs access to all of the readily available editions of the interpreter but also to earlier versions that are no longer… Read
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Technical advice and assistance on all aspects of Dyalog usage is available by e-mail (support@dyalog.com) and/or telephone (+44 1256 830030 – limited to U.K. office hours). Limited advice on design and coding is available, but is not intended to replace the use of the printed and on-line documentation. Except when reporting an issue with the software, users are encouraged to seek advice from the user community via the Dyalog Forum (reading the content of the forums does not require membership).

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