Line plot: Support multiple (up to 5) derived curves

[bikegeek]

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Describe the New Feature

The line plot currently supports only derived curves which is inconsistent with what METviewer can support. In an effort to provide command line support for plotting that equals what is available in METviewer, add support for up to five derived curves (for some users, 3 derived curves are sufficient). Support for more than five curves will result in a cluttered plot and does not provide much value.

Acceptance Testing

List input data types and sources.
Describe tests required for new functionality.

Time Estimate

Estimate the amount of work required here.
Issues should represent approximately 1 to 3 days of work.

Sub-Issues

Consider breaking the new feature down into sub-issues.

• Add a checkbox for each sub-issue here.

Relevant Deadlines

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Funding Source

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Define the Metadata

Assignee

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• Select scientist(s) or no scientist required

Labels

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Projects and Milestone

• Select Repository and/or Organization level Project(s) or add alert: NEED CYCLE ASSIGNMENT label
• Select Milestone as the next official version or Future Versions

Define Related Issue(s)

Consider the impact to the other METplus components.

• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

New Feature Checklist

See the METplus Workflow for details.

• Complete the issue definition above, including the Time Estimate and Funding source.
• Fork this repository or create a branch of develop.
  Branch name: feature_<Issue Number>_<Description>
• Complete the development and test your changes.
• Add/update log messages for easier debugging.
• Add/update unit tests.
• Add/update documentation.
• Add any new Python packages to the METplus Components Python Requirements table.
• Push local changes to GitHub.
• Submit a pull request to merge into develop.
  Pull request: feature <Issue Number> <Description>
• Define the pull request metadata, as permissions allow.
  Select: Reviewer(s) and Development issues
  Select: Repository level development cycle Project for the next official release
  Select: Milestone as the next official version
• Iterate until the reviewer(s) accept and merge your changes.
• Delete your fork or branch.
• Close this issue.