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JiaweiZhuang / xESMF

Universal Regridder for Geospatial Data
http://xesmf.readthedocs.io/
MIT License
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Possibly incorrect terminology in documentation #40

Closed JanisGailis closed 5 years ago

JanisGailis commented 5 years ago

This is a documentation issue.

I believe you have mixed up the terms 'downsample' and 'upsample' in documentation. It is said:

When regridding from low-resolution to high-resolution (down-sampling)

And:

When regridding from high-resolution to low-resolution (up-sampling)

But the opposite seems to be the generally accepted definition: https://en.wikipedia.org/wiki/Decimation_(signal_processing) https://en.wikipedia.org/wiki/Upsampling

Going from low-res (coarse) grid to high-res (fine) grid increases the sampling rate => 'upsampling'. Going from high-res (fine) grid to low-res (coarse) grid reduces the sampling rate => 'downsampling'

Let me know if I'm wrong and I have mixed up the terms myself!

JiaweiZhuang commented 5 years ago

Good catch!

I should have used "downscaling" instead of "downsampling". The former is a climate modeling term while the latter comes from signal processing. Confusingly, "downscaling" is actually equivalent to "upsampling", both referring to "increasing resolution".

From wiki:

Downscaling is any procedure to infer high-resolution information from low-resolution variables.

upsampling can refer to the entire process of increasing the sampling rate of a signal

JiaweiZhuang commented 5 years ago

So I decided to avoid using either "downsampling" or "downscaling" in the docs. Simply using "Increasing/Decreasing resolution" should be the least confusing...

Thanks for pointing this out!