# Julia NDTensors development

**URL:** <https://itensor.discourse.group/t/julia-ndtensors-development/511>\
**Category:** ITensor Development\
**Tags:** julia\
**Created:** [November 11, 2022, 9:16pm UTC](https://itensor.discourse.group/t/julia-ndtensors-development/511 "2022-11-11T21:16:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![JanReimers](https://yyz2.discourse-cdn.com/free1/user_avatar/itensor.discourse.group/janreimers/32/171_2.png) [@JanReimers](https://itensor.discourse.group/u/JanReimers)\
**Post date:** [November 11, 2022, 9:16pm UTC](https://itensor.discourse.group/t/julia-ndtensors-development/511/1 "2022-11-11T21:16:00Z")

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The AdvancedUsageGuide gives excellent instructions for developing inside ITensors.jl, the secret sauce being command:  
Pkg.develop(url=“[https://github.com/[MyGitHubForkLocation]/ITensors.jl](https://github.com/%5BMyGitHubForkLocation%5D/ITensors.jl)”)

As part of implementing Block sparse QR/QL/RQ/LQ decompositions I will need to add some code to NDTensors. I am finding that changes inside my local NDTensors (inside my ITensors.jl fork) has no effect at run time. The system seems to prefer to grab and compile from the official repo instead. I tried the command

`Pkg.develop(url="https://github.com/JanReimers/ITensors.jl/tree/main/NDTensors")`

Cloning git-repo `https:github.com/JanReimers/ITensors.jl/tree/main/NDTensors`  
ERROR: failed to clone from https:github.com/JanReimers/ITensors.jl/tree/main/NDTensors, error: GitError(Code:ERROR, Class:HTTP, unexpected http status code: 404)

How do the insiders set up julia to work the local NDTensors source tree?

Thanks

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<div class="post-metadata">

**Author:** ![ryanlevy](https://yyz2.discourse-cdn.com/free1/user_avatar/itensor.discourse.group/ryanlevy/32/150_2.png) [@ryanlevy](https://itensor.discourse.group/u/ryanlevy)\
**Post date:** [November 16, 2022, 9:50pm UTC](https://itensor.discourse.group/t/julia-ndtensors-development/511/2 "2022-11-16T21:50:01Z")

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I’m not a julia expert, but

```auto
pkg> dev https://github.com/JanReimers/ITensors.jl NDTensors

```

or

```auto
Pkg.develop(url="https://github.com/JanReimers/ITensors.jl", subdir="NDTensors")

```

For local directories just cd into the appropriate folder and in package mode do `pkg> dev .` (my preferred method)

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<div class="post-metadata">

**Author:** ![JanReimers](https://yyz2.discourse-cdn.com/free1/user_avatar/itensor.discourse.group/janreimers/32/171_2.png) [@JanReimers](https://itensor.discourse.group/u/JanReimers)\
**Post date:** [November 16, 2022, 9:57pm UTC](https://itensor.discourse.group/t/julia-ndtensors-development/511/3 "2022-11-16T21:57:30Z")

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OK that works … thank you!