# Implementing simple quadratic interpolation in Interpolations.jl

**URL:** <https://discourse.julialang.org/t/implementing-simple-quadratic-interpolation-in-interpolations-jl/129555>\
**Category:** Specific Domains\
**Tags:** interpolations\
**Created:** [June 2, 2025, 12:02pm UTC](https://discourse.julialang.org/t/implementing-simple-quadratic-interpolation-in-interpolations-jl/129555 "2025-06-02T12:02:40Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![xor0110](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/xor0110/32/7926_2.png) [@xor0110](https://discourse.julialang.org/u/xor0110)\
**Post date:** [June 2, 2025, 12:02pm UTC](https://discourse.julialang.org/t/implementing-simple-quadratic-interpolation-in-interpolations-jl/129555/1 "2025-06-02T12:02:40Z")

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I’m looking for advice about implementing simple quadratic and cubic interpolations into Interpolations.jl. These are interpolation methods that should work similar to linear interpolation, with no pre-filtering necessary and values computed straight from the original data. The paper “Quadratic Interpolation for Image Resampling” (Dodgson 1997) has the formulas. What are the required steps to implement a new method like this? Would that really be the best package to contribute this in the first place?

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**Author:** ![marcobonici](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/marcobonici/32/20549_2.png) [@marcobonici](https://discourse.julialang.org/u/marcobonici)\
**Post date:** [June 2, 2025, 12:19pm UTC](https://discourse.julialang.org/t/implementing-simple-quadratic-interpolation-in-interpolations-jl/129555/2 "2025-06-02T12:19:47Z")

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Hi! My suggestion is also to look into [DataInterpolations.jl](https://github.com/SciML/DataInterpolations.jl). They already have quadratic and cubic interpolators (and it should work nicely with AD systems).  
Notice that this is meant to be a 1D interpolation package, don’t know whether this meets your requirements.

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**Author:** ![xor0110](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/xor0110/32/7926_2.png) [@xor0110](https://discourse.julialang.org/u/xor0110)\
**Post date:** [June 2, 2025, 12:32pm UTC](https://discourse.julialang.org/t/implementing-simple-quadratic-interpolation-in-interpolations-jl/129555/3 "2025-06-02T12:32:59Z")

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That looks cool, but I am indeed interested in interpolating images, and I’m not sure how easy is to do that with any other package.