[gdal-dev] gdal_grid: number of data points to use

[Even Rouault]

Le samedi 18 janvier 2014 12:48:23, Jan Hartmann a écrit :
> gdal_grid has the option to set a minimum and maximum number of data
> points to use for interpolation. How are these data points selected from
> the total number of points? Are they always the nearest points to the
> grid-point that is interpolated?

Jan,

if less than min_points match the selection of the algorithm, the nodata value 
will be returned
and when iterating over source points (in the order they are present in the 
source OGR layer), the algorithm will stop as soon as max_points is reached. 
The selected points are consequently not necessarily the nearest points, but 
they will be contained in the search ellipse (since max_points is only taken 
into account if you define radius1 and radius2)

Even

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