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seen Jan 27 at 4:49

Jan
14
answered How to compute area for polygons in an EPSG:4326 shapefile?
Jan
14
comment How to calculate area in km2 Qgis 2.0
There seems to be some room for doubt: 0.004008*cos(latitude)(1.852*60)^2=49.4894km^2 at latitude=0, and there's no latitude where the area will be 1.017* bigger than the equatorial area in decimalDegrees^2.
Jan
8
answered Viewing/understanding NetCDF files
Jan
7
awarded  Yearling
Jan
7
awarded  Necromancer
Nov
19
comment How to easily shift all features in a vector dataset?
Brilliant -- a simple one line CLI solution.
Aug
12
answered gdal_grid unable to get nodata outside of original data area
Aug
12
answered gdal_grid failing to set nodata
Aug
11
comment Writing numpy array to raster file
The "rotation is in twice" to account for the effect of a rotated bit of y on x and the rotated bit of x on y. See lists.osgeo.org/pipermail/gdal-dev/2011-July/029449.html which tries to explain the interrelationships between the "rotation" parameters.
Aug
5
revised Bilinear interpolation of point data on a raster in Python?
deleted 2 characters in body
Aug
5
answered Bilinear interpolation of point data on a raster in Python?
Aug
5
answered gdal_grid has some problem with reading vrt file
Aug
4
comment gdal_grid failing to set nodata
They might be thinking of this as a default value to store in the array, while identifying that value as flag for nodata value is a separate function. That said, one would think that this might work: ######################## gdal_grid -co PROFILE=GDALGeoTIFF -co TIFFTAG_GDAL_NODATA=-9999 .... ############# but with gdal 11.1 it fails with "Warning 6: Driver GTiff does not support TIFFTAG_GDAL_NODATA creation option"
Aug
4
comment Bilinear interpolation of point data on a raster in Python?
ax,ay might have a problem if the grid is rotated at all. It might be better to transform your interpolate-to points into pixel or data coordinates. Also, if there is an off-by-one problem with them, then you might be going beyond the size of the band.
Aug
1
comment What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?
combine looks like it would merge the parts, losing their individual identities. I don't want them merged into one, I want a new multipart geometry.
Aug
1
comment Negative UTM easting
110,000m/1852/60 = 0.998 degrees wide, which is too narrow. 6 degrees would be about 6*1852*60=666,720m wide.
Jul
30
comment What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?
My motivation is the same specified distance redistributing-vertices use-case as in gis.stackexchange.com/q/107999/10229 but I'd like to know how to write things to deal with polygons, and potentially 2.5D polygons and polylines as well. (Ultimately, I need to redistribute the vertices unevenly, based on a raster or some function of a raster, but that's for later.)
Jul
30
revised What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?
expand the question
Jul
30
comment What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?
No, I do not want to replace the multipart with a set of component parts (like 'explode' ungroup, or multi-to-single). I want to unpack the multigeom into its component parts, apply a user-defined function (in the Q, myFunction() is an identity function as a , but a function like reverse_line(), densify(), simplify()) to the parts to make a set of new parts, then re-pack the new parts into a new, replacement multigeom to use as a replacement. In your answer, how do I append each g.exportToWkt() into a list, and convert the list back into a multipart geometry of the same type as geom?
Jul
25
revised What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?
added 168 characters in body