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4

This was a tough problem to track down because I had thought that the effect was at the edges of tiles when it fact they are throughout the data. You're right that the phenomena isn't in the data before mosaicking the data. The problem results from the resampling process that is inherent in mosaicking. You need to use either the cubic convolution or bilinear ...


2

In ArcGIS, use the Resample tool to resample two of the three rasters into a cell size that matches the third on. You'll need to consider what you're doing to your data when you resample. With that in mind I would pick the Land Use raster as the one that goes unmodified since the others are likely already interpolations of discrete samples of continuous ...


1

The tool you are looking for is called Mosaic to new raster. It sits in the Data management toolbox under Raster/Raster Dataset. If your rasters are all neatly aligned, you don't have to worry about the mosaic operator. However if any of the rasters overlap, the mosaic operator gives you the ability to choose which value or which raster should get ...


5

You can use Mapshaper for this, and then dissolve from the command line: mapshaper --dissolve -i your_data.geojson


2

It's easy to do with QGis. Open QGis Drag&Drop the geojson file to qgis use the "dissolve" tool in the vector menu (it's inside a submenu). use the "dissolve all" option from the dropdown this will create a shapefile (check the box to output to the map) which you can then again save as a geojson file by right-clicking it in the layer pane and choosing ...


0

Wondering if the issue could be with rasters that are derived from elevations (curvature) rather than the original dem data. Some issue similar to hill shade rasters, which can be problematic to mosaic as mentioned here 'HILLSHADE NOTE: (Do not MOSAIC hillshades: MOSAIC the DEM's first and then create a hillshade). When working with multiple DEM files, it ...


1

MMQGIS plugin have your merge funcion... other merge funcion can be found in Processing/gdal Processing/saga but MMGIS works as you aspected


1

Easy, use ST_LineMerge with the MultiLineString geometry. SELECT ST_LineMerge(geom) FROM ... Returns a LineString if it is possible, such is the example in the question.


0

Simply copy and paste the features from one layer to the other. The second one must be in edit mode for that. Just as you would do with a text editor. Or take the whole world shapefile from Natural Earth, select the two and export the selection to another file.


1

I've analysed the geometry issues in the attached data, and it seems it does not ONLY have orphaned holes but also geometry validity issues. It's true that an orphaned hole is somehow a geometry validity issue, but rgeos does not handle it in the same way, as for orphaned holes, an error is raised, instead of a simple warning. As you indicate, they are hints ...



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