edited echelle_diagram to make it faster

[MaryumSayeed]

...based on Yaguang & Courtney's code

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name: Pull request
about: Contribute to this project!
title: ''
labels: ''
assignees: ''

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Relevant Materials

Description

Using the checklist as a guide, please provide more details about the nature of the pull request.

Attachments & Supporting Files

Please provide any relevant files i.e. data if adding a new target to a test or as an example

Other

Any other relevant context i.e. reference/link if directly addressing an existing issue

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Summary Checklist:

• Is this a major request?
  • Yes
    → Have you already submitted an issue outlining the request?
    • Yes
    • No
  • No
  • IDK
• What type of request is this?
  • New feature
  • Modification
  • Suggested update
  • Other*
• Why is the change needed?
  • General improvement
  • Solves a problem
  • Relevant to an open issue
    → Did you provide the link?
    • Yes
    • No
  • Increased efficiency and/or speed
  • Other?*
• Did you test your changes?
  • Yes
  • No (please do not submit a request until you have)
  • N/A
• Does the code comply with our style guide and is it complete with docstrings and other relevant documentation?
  • Yes
  • No
• Will this request require any changes from our end?
  • Yes**
  • No

* If 'Other' was selected at any point, please expand on each of these points in more detail below.
** If 'Yes' was selected for the last bullet, please elaborate below.

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