eo_over()

Overlays two geographically referenced arrays and returns array coordinates of the target array which overlay specific cells of the source array.

Synopsis

AFL% eo_over(A, B);

Argument	Description
`A`	Source array
`B`	Target array

Result

The result array has the same dimensionality and the same number of cells as the source array A. Attribute values of result cells are coordinates of B at which A and B mutually overlay. Depending on the setting of A and B, The output always contains 4 attributes over_x, over_y, over_t, and over_v. Depending on the setting of A and B, i.e. whether the arrays have spatial, temporal, spatiotemporal, or even vertical geographic reference, particular attributes values might be null for all cells.

Details

This operator can be used to insert earth-observation data by tiles, and spatiotemporally joining datasets for statistical analyses.

Examples

Insert two temporal slices into a three dimensional array. ``` store(build([lat=0:1799,256,0,lon=0:3599,256,0, t=0:364,16,0],1),world_jan1);
eo_setsrs(world,‘lon’,‘lat’,‘EPSG’,4326,‘x0=-180 y0=90 a11=0.1 a22=-0.1’); eo_settrs(world,‘t’,‘2015-01-01’, ‘P1D’);

store(build([lat2=0:1799,256,0,lon2=0:3599,256,0, t2=0:364,16,0],2),world_jan2);
eo_setsrs(world,‘lon2’,‘lat2’,‘EPSG’,4326,‘x0=-180 y0=90 a11=0.1 a22=-0.1’); eo_settrs(world,‘t2’,‘2015-01-02’, ‘P1D’);

insert(redimension(attribute_rename(join(world_jan2, eo_over(world_jan2,world_jan1)), over_x, x, over_y, y, over_t, t), world_jan1), world_jan1); ```

Notes

Author(s)

Marius Appel - marius.appel@uni-muenster.de