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Questions tagged [anamorphism]

In functional programming, an anamorphism is a generalization of the concept of unfolds on lists.

In functional programming, an anamorphism is a generalization of the concept of unfolds on lists. Formally, anamorphisms are generic functions that can corecursively construct a result of a certain type and which is parameterized by functions that determine the next single step of the construction.

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What is an anamorphism, and how does one look like in C#?

I am trying to wrap my head around the concept of anamorphism. In functional programming, an anamorphism is a generalization of the concept of unfolds on lists. Formally, anamorphisms are generic functions that can corecursively construct a result…
Jaanus Varus
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Memoizing a recursion scheme

Is it possible to memoize a recursion scheme? If so, how would you? For example, the following uses anamophism and catamorphism newtype Fix f = In (f (Fix f)) deriving instance (Eq (f (Fix f))) => Eq (Fix f) deriving instance (Ord (f (Fix f))) =>…
cocorudeboy
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Haskell monadic parser with anamorphisms

My problem is how to combine the recursive, F-algebra-style recursive type definitions, with monadic/applicative-style parsers, in way that would scale to a realistic programming language. I have just started with the Expr definition below: data…
Matei
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Swift Sequence Anamorphism

Does Swift's standard library include a list anamorphism for a Sequence or something similar? An Anamorphism on lists or sequences would be the opposite of the reduce function. So instead of collapsing a sequence down to a single value, it will…
Benjohn
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Haskell - Expressing the Depth First Traversal of a Rose Tree as an instance of unfold, deriving it algebraically

Suppose we have a Rose Tree defined, along with the corresponding fold over the datatype. data RTree a = Node a [RTree a] foldRTree :: (a -> [b] -> b) -> RTree a -> b foldRTree f (Node x xs) = f x (map (foldRTree f) xs) A recursive definition of a…
samlu1999
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Writing zip (longzip) using an anamorphism

Working on a project and trying to write longzip using an anamorphism. I'm having some trouble writing a coalgebra for this use case. I've defined my anamorphism in terms of Fix below: -- Fixed point of a Functor newtype Fix f = In (f (Fix f)) …
Conor Quinn
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A recursion scheme from Int -> Int?

The foldr identity is foldr (:) [] More generally, with folds you can either destroy structure and end up with a summary value or inject structure in such a way that you end up with the same output structure. [Int] -> [Int] or [Int] ->…
Conor Quinn
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Repetitions as an Hylomorphism

So I've been trying to convert this Haskell function thats checks if a list doesn't have any repetitions into an Hylomorphism, but there's something odd about it. valid :: [a] -> Bool valid [] = True valid (h:t) = if (not (elem h t)) then valid t…
João Pimentel
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How can I Create 3D Billboard Curved Screen Using Unity?

I want Create Digital Signage like this picture for 3D Billboard Curved Screen using Unity. I found method for make that. Renders the camera at a three-dimensional angle. Map the rendered image once to a screen object in the camera position. Burn…
MayQuartet
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anam/phantommagick - Binary does not exist in server Oracle Linux Server 7.6

I am working laravel project, I convert the view page as an image using anam/phantommagick package enter link description here. It Working fine in my local system (Ubuntu 16.04.6 LTS).But move the server it's not working. i got below error I added…
Selvamani P
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Anamorphosis in Python

I tried to do anamorphosis on an image by following this link https://github.com/aydal/Cylinderical-Anamorphosis/blob/master/anamorph.py It gives an anamorphic image but it gives that image in the half circle. But I want the output in a full circle…
Nihar
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