# \#lazy

**URL:** https://discourse.julialang.org/tag/lazy/1180.md

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## [Virtual (or lazy) representation of a repeated array](https://discourse.julialang.org/t/virtual-or-lazy-representation-of-a-repeated-array/124954)

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**Author:** [@Alexander-Barth](https://discourse.julialang.org/u/Alexander-Barth)\
**Replies:** 4\
**Last updated:** [January 22, 2025, 12:22pm UTC](https://discourse.julialang.org/t/virtual-or-lazy-representation-of-a-repeated-array/124954 "2025-01-22T12:22:50Z")

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Is there an array type, that allows me to create a virtual (or lazy) representation of the following array x ? sz = (64, 64, 2, 10589) tmp = reshape(range(-1,1,64),(:,1,1,1)); x = repeat(tmp,1,sz\[2\],sz\[3\],sz\[4\]); It …

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## [Iterative construction of lazy Iterators leads to excessive compilation time](https://discourse.julialang.org/t/iterative-construction-of-lazy-iterators-leads-to-excessive-compilation-time/106766)

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**Author:** [@\_cao](https://discourse.julialang.org/u/_cao)\
**Replies:** 21\
**Last updated:** [December 10, 2023, 8:19pm UTC](https://discourse.julialang.org/t/iterative-construction-of-lazy-iterators-leads-to-excessive-compilation-time/106766 "2023-12-10T20:19:00Z")

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I wanted to write an iterator that lazily traverses a graph in breadth first search order, where the graph is defined implicitly by a function giving for each vertex an iterable over the adjacent vertices. This is what I…

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## [Lazy broadcasting speed issues](https://discourse.julialang.org/t/lazy-broadcasting-speed-issues/94218)

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**Author:** [@RainerHeintzmann](https://discourse.julialang.org/u/RainerHeintzmann)\
**Replies:** 13\
**Last updated:** [March 12, 2023, 4:52pm UTC](https://discourse.julialang.org/t/lazy-broadcasting-speed-issues/94218 "2023-03-12T16:52:22Z")

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I am working on a new package called SeparableFunctions.jl with the aim to boost the performance for functions which are expensive to calculate on multidimensional grids, but can profit a lot from broadcasting. To this…

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## [Broadcasting and piping](https://discourse.julialang.org/t/broadcasting-and-piping/89542)

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**Author:** [@Lincoln\_Hannah](https://discourse.julialang.org/u/Lincoln_Hannah)\
**Replies:** 4\
**Last updated:** [October 31, 2022, 11:22pm UTC](https://discourse.julialang.org/t/broadcasting-and-piping/89542 "2022-10-31T23:22:25Z")

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The basic pipe operator allows for broacasting e.g. 1:5 .|\> exp As far as I know @chain and Lazy @\> don’t support this. You can get around this by defining. ⬅map(a,b) = map(b,a) and writing @\> 1:5 …

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## [Computing array elements on call](https://discourse.julialang.org/t/computing-array-elements-on-call/1918)

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**Author:** [@andremanoel](https://discourse.julialang.org/u/andremanoel)\
**Replies:** 7\
**Last updated:** [February 5, 2017, 4:49pm UTC](https://discourse.julialang.org/t/computing-array-elements-on-call/1918 "2017-02-05T16:49:14Z")

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Hello, I’d like to have an array which elements A\[i, j\] are computed from a given function f(i, j) (say f(i, j) = i + j) only when that element is used, i.e. I would not like to build the whole matrix beforehand. I was…