[GPlates-discuss] Convert reconstructed points back to raster

[John Cannon]

Hi Aleece,

If you're using GMT then perhaps 'nearneighbor' could be used:
https://protect-au.mimecast.com/s/FlEtCANZvPiQ21l6cG9SXa?domain=gmt.soest.hawaii.edu

You first need to store your points (and raster z values) in an xyz text file with 3 columns (longitude, latitude, z). Then pass that to 'neighneighbor':

  gmt nearneighbor <xyz_filename> -N4 -S<1.5 * grid_spacing> -I<grid_spacing> -R-180/180/-90/90 -G<grid_filename>

...with '<...>' replaced with your own values.

I find the search radius (-S) of 1.5 times grid spacing to work fairly well in general. The data points (at the 'from' time) are no longer uniform (like at the 'to' time), so some interpolation smoothing is inevitable.

Regards,
John

From: GPlates-discuss <gplates-discuss-bounces at mailman.sydney.edu.au> On Behalf Of Nanfito, Aleece
Sent: Thursday, 5 September 2019 7:38 AM
To: gplates-discuss at mailman.sydney.edu.au
Subject: [GPlates-discuss] Convert reconstructed points back to raster

Hello -

I am looking for some help with converting reconstructed points back to a raster in pyGPlates. I received some excellent guidance from this group a few months ago on how to convert a raster (paleo-position) to points and then un-reconstruct the points to present day, but I am missing the part on how to convert the output points back to a raster.  I would like the new raster to be the same resolution as the input raster and to minimize any interpolation or extrapolation of the point data.

Apologies if this was answered in responses to my first question, but I am struggling to identify this last step. I appreciate any input and thanks so much in advance!

Best regards,
Aleece


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Aleece Nanfito
Geologist
aleece.nanfito at bhp.com<mailto:aleece.nanfito at bhp.com>
T +1 713 499 5488
M +1 402 995 1976
1500 Post Oak Blvd.
Houston TX 77056 USA

bhpbilliton.com<https://protect-au.mimecast.com/s/1EMvCBNZwLiGBlR6u678Wo?domain=bhpbilliton.com>


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