New ``model.missing_value``

[einola]

New model.missing_value

Fixes #612

Task List

• [x] Defined the tests that specify a complete and functioning change (It may help to create a design specification & test specification)
• [x] Implemented the source code change that satisfies the tests
• [x] Documented the feature by providing worked example
• [ ] Updated the README or other documentation
• [x] Completed the pre-Request checklist below

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Change Description

This PR changes the value of model.missing_value to be less than the largest permitted float on most systems. This is so that we can easily view the netCDF files output by the model using ncview.

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Test Description

Run the dynamics benchmark (./nextsim --config-files config_benchmark.cfg) and view the output using ncview. An ncdump -h benchmark_32x32.diagnostic.nc| grep 'missing_value' should look like this:

                cice:missing_value = 1.7e+38 ;
                hice:missing_value = 1.7e+38 ;
                hsnow:missing_value = 1.7e+38 ;
                u:missing_value = 1.7e+38 ;
                v:missing_value = 1.7e+38 ;

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Documentation Impact

N/A

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Other Details

None

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Pre-Request Checklist

• [x] The requirements of this pull request are fully captured in an issue or design specification and are linked and summarised in the description of this PR
• [x] No new warnings are generated
• [x] The documentation has been updated (or an issue has been created to track the corresponding change)
• [x] Methods and Tests are commented such that they can be understood without having to obtain additional context
• [x] This PR/Issue is labelled as a bug/feature/enhancement/breaking change
• [x] File dates have been updated to reflect modification date
• [x] This change conforms to the conventions described in the README