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5

The answer is Pyproj. Transforms lists of coordinates in a single call, and since it's a C extension module that uses PROJ.4, the same results as cs2cs but at C speed.


3

You need to apply the geographic transformation too. In the 10.2.5 API, project has several versions. You're going to have to switch to one that uses a Geometry and supports a GeographicTransformation instead like: public static Geometry project (Geometry geometry, SpatialReference inputSR, SpatialReference outputSR, GeographicTransformation tx) For the ...


3

You are correct to use an appropriate projection for computing slope and aspect. The problems occur when reprojecting those results to another coordinate system (such as lat-lon). Two things happen: Grid values must be resampled in order to interpolate them to the new cell centers. Aspects, being circular data, must be specially handled. Otherwise the ...


3

I believe the problem might be in your coordinate system definitions -- ref. the Project Raster help page. The coordinate system to which the input raster will be projected. The default value is set based on the Output Coordinate System environment setting. Valid values for this parameter are A file with the ".prj" extension (the prj ...


2

I have put a projection setting in your source definition and it seems to work: var vS=new ol.source.GeoJSON( ({ "object": data, projection: 'EPSG:3857' }) ); This is the result: http://jsfiddle.net/zzahmbff/3/ Perhaps this resource can help you to see different ways to load vector data: ...


2

The part that is going wrong is where you assumed that the coordinates in 3857 are degrees (like -5.8, 41). The units of 3857 are metres. So you're asking for something tiny, off the map (near the origin). Lets look at a conversion, using pyproj: from pyproj import Proj, transform inProj = Proj(init='epsg:4326') outProj = Proj(init='epsg:3857') x1,y1 = ...


1

The scale option is only needed for "unprojected" rasters with units in degrees. It is the ratio of height units used in the DEM (typically meters) to distance units in degrees. So for Mercator or other projected rasters, you can ignore the scale option, or use the default of 1 (no scale).


1

If you have to deal with the whole United States, you should use one of the Contiguos projections: ESRI:102003 USA_Contiguous_Albers_Equal_Area_Conic ESRI:102004 USA_Contiguous_Lambert_Conformal_Conic ESRI:102005 USA_Contiguous_Albers_Equal_Area_Conic You can reproject your UTM data to one of those CRS, then combine them.


1

Here's a working script. I started from the modelbuilder code for reprojecting a single raster, and incrementally changed inputs to variables testing at each step. Seemingly the only difference between the working script below and my previous non-functioning script is that the variables are defined within the body of the for loop. I've also added some ...


1

The metadata of the netcdf file includes projection information, which can be identified by QGIS as a custom CRS: +proj=lcc +lat_1=50 +lat_2=50 +lat_0=50 +lon_0=-107 +x_0=5632642.22547 +y_0=4612545.65137 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs but there is no extent given in projection units, only latlon for the corners. If you run gdalinfo ...


1

Projecting a raster results in a resampling/alteration of the values in that raster because the size/shape/number of cells are changed. It's basically creating a whole new raster and interpolating the values of the new cells based on how that grid lines up with the source grid. The help file usage notes describe some of the issues involved in detail.



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