006 feature sampler near land

[b-barton]

This fixes #6 . The code now account for profiles that are sampled on the model grid and fall on land. These profiles are rejected and not returned in the dataset of model profiles.

[atb299]

The code all reads OK to me, so I think it is OK to be merged. I will leave that step for Ollie, since this will be merged with main and I am still not entirely familiar with the repo.

[oj-tooth]

Happy with this PR, but wanted to pose my question on where the land-sea filtering implementation should happen before we merge into main?

It may be possible to move this filtering earlier in the ObsSampler lifecycle, ensuring we do not generate any (j, i) model coordinates for synthetic profiles that are located on land and then filtering during extraction would not be needed.

Would be good to get @b-barton and @atb299 thoughts on this?

[b-barton]

I think the nearest neighbour sampler sits in parallel to the RandomSampler. In config you will pick which route your going. I thought either you pass it a dataset of profiles you want to replicate in model space or you want a random set from the probability distribution?

For the wet cell filtering, I think it need to happen in both places.
Off issue but the probability map doesn't necessarily correspond to the model grid you want to apply it to so they might have different land masks. The probability map gets interpolated to the model grid.

If there is a better place for it, it could get moved later. I'm not sure where that would be though because before ObsSampler is DataLoading.

[oj-tooth]

Looks good to me!

Let's get this into main and work on testing the complete OceanOSSE pipeline.