[postgis-devel] [PostGIS] #795: [raster] ST_Intersects raster documentation is confusing

[PostGIS]

#795: [raster] ST_Intersects raster documentation is confusing
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 Reporter:  pracine         |       Owner:  pracine      
     Type:  enhancement     |      Status:  new          
 Priority:  medium          |   Milestone:  PostGIS 2.0.0
Component:  postgis raster  |     Version:  trunk        
 Keywords:                  |  
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Description changed by pracine:

Old description:

> The description says: "Returns true if any pixel in a raster band has a
> value that is not nodatavalue and that geometry region of the pixel
> intersects the geometry. If hasnodata is passed in, then it will use that
> to consider if it needs to analyze pixels (true) means analyze pixels, if
> the convexhull intersects the geometry. false means just return true if
> the convex hull of the raster intersects with the geometry. If hasnodata
> is omitted, it reads the value from the meta data of the raster."
>
> The last part of the sentence is false.
>
> Better proposition:
>
> -"Returns true if the geometry intersects with the raster. Nodata values
> are taken into account so that if the geometry intersects only with
> nodata values, the function returns false. hasnodata may modify this
> behavior: if set to false, nodata value are not taken into account and
> the function returns true as soon as the geometry intersects with the
> convex hull of the raster."

New description:

 The description says: "Returns true if any pixel in a raster band has a
 value that is not nodatavalue and that geometry region of the pixel
 intersects the geometry. If hasnodata is passed in, then it will use that
 to consider if it needs to analyze pixels (true) means analyze pixels, if
 the convexhull intersects the geometry. false means just return true if
 the convex hull of the raster intersects with the geometry. If hasnodata
 is omitted, it reads the value from the meta data of the raster."

 The last sentence is false.

 Better proposition:

 -"Returns true if the geometry intersects with the raster. Nodata values
 are taken into account so that if the geometry intersects only with nodata
 values, the function returns false. hasnodata may modify this behavior: if
 set to false, nodata value are not taken into account and the function
 returns true as soon as the geometry intersects with the convex hull of
 the raster."

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/795#comment:1>
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