Questions tagged [apl]
This challenge is related to APL (A Programming Language). Note that challenges that require the answers to be in a specific language are generally discouraged.
15
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Evaluation order of an APL n-train
From Codidact with permission.
Description
APL trains are a series of functions, that get applied to an argument in this way:
(f g) x = f g x here ...
- 29.9k
25
votes
10
answers
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Floor of complex number
Background
Complex floor is a domain extension of the mathematical floor function for complex numbers. This is used in some APL languages to implement floor ⌊, ...
- 73.8k
40
votes
38
answers
3k
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Ken Iverson’s Favourite APL Expression?
Ken Iverson, 1920–2020
Let's implement his favourite expression:
Given a row of Pascal's triangle, compute the next row.
This can for example be computed by taking the input padded with a zero on the ...
- 29.9k
18
votes
7
answers
870
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What valence does this APL train have?
Context
In APL, trains are tacit sequences of monadic/dyadic functions that can be called with one or two arguments. We'll code something to check if a given train follows the correct structure we ...
- 14k
15
votes
6
answers
773
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Implement 1-dimensional version of Multi-Take
Background
Adám and I were once discussing a way to properly extend some features in Dyalog APL. I came up with the following extension to Take, a function that takes some front or back elements (and ...
- 73.8k
14
votes
2
answers
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Explicit-ify APL expressions involving trains
Related: Clearly parenthesize APL trains
Background
In the most basic form, APL has two kinds of tokens: arrays and functions. For this challenge, we will use a lowercase letter ...
- 73.8k
19
votes
4
answers
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What have we got?
Inspired by, and in memory of, our beloved genius,
R.I.P.
He invented and implemented dfns — his magnum opus and the subject of the challenge.
For the interested: latest full dfns documentation and ...
- 29.9k
16
votes
5
answers
368
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Conjugation in Real Life
In @Adám's Dyalog APL Extended, the ⍢ (under) operator means conjugation: apply one function, then a second function, then the inverse of the first. It's fun to ...
- 21.4k
9
votes
1
answer
431
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Dyadic Transpose
As with most APL symbols, ⍉ has different meanings when called with one argument (transpose) versus two arguments (dyadic transpose / reorder dimensions). This ...
- 21.4k
24
votes
3
answers
1k
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Clearly parenthesize APL trains
In APL, you can write tacit functions, called trains. How they work is irrelevant for this challenge. Here are the different ways they can be grouped, using ⍴ as ...
- 40.5k
8
votes
7
answers
497
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Fill the steps (randomly)!
This is Hole-9 from The Autumn Tournament of APL CodeGolf. I am the original author of the problem there, and thus allowed to re-post it here.
Given a simple (rectangular, non-jagged) Boolean array (...
- 29.9k
13
votes
17
answers
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Ten-row bar chart
This is Hole-1 from The Autumn Tournament of APL CodeGolf. I am the original author of the problem there, and thus allowed to re-post it here.
Given a list of numbers, produce a horizontal bar chart ...
- 29.9k
25
votes
8
answers
2k
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Take that frown and turn it around
A celebration of the many faces of APL
Given a string among those in column 1 or column 2 of the below table, return the string's neighbor to its right. In other words, if given a string in column 1 ...
- 29.9k
26
votes
11
answers
2k
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Official Dyalog APL 2016 Year Game
If you think this could be fun, but too much work, consider participating in this much smaller challenge.
A bit of fun (and possibly frustration!) for 2016... Dyalog's "puzzle of the year". ...
- 29.9k
43
votes
18
answers
5k
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Tips for golfing in APL
I started one code golf challenge recently and it seems like the winner is GolfScript (surprise, surprise!). What's interesting is that there was another very strong competitor that had all chances to ...
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