# New array from a sum of N values in array A?

**URL:** <https://discourse.julialang.org/t/new-array-from-a-sum-of-n-values-in-array-a/46496>\
**Category:** General Usage\
**Tags:** tullio\
**Created:** [September 12, 2020, 6:10am UTC](https://discourse.julialang.org/t/new-array-from-a-sum-of-n-values-in-array-a/46496 "2020-09-12T06:10:29Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![xiaodai](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/xiaodai/32/15937_2.png) [@xiaodai](https://discourse.julialang.org/u/xiaodai)\
**Post date:** [September 12, 2020, 7:37am UTC](https://discourse.julialang.org/t/new-array-from-a-sum-of-n-values-in-array-a/46496/3 "2020-09-12T07:37:10Z")

</div>

rolling sum or moving sum?

See [Rolling Sum](https://discourse.julialang.org/t/rolling-sum/30793)

I think Tullio has an interesting solution

```julia
A = rand(100_000_000);

using Tullio

N = 3
res = zeros(eltype(A), length(A))

using Tullio
@time @tullio res[j] = A[j] + A[j+1] + A[j+2]
@time @tullio res[j] = A[j] + A[j+1] + A[j+2] # 0.2s

```

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