[GIS] How to create rendered vector field in qgis

netcdfqgisrastervector

Perhaps I am misunderstanding the "vector field renderer" and "VectFieldCalc" plugins, but I have no idea how to make a vector field of arrows, with directions and magnitude. I have the data loaded currently with two seperate .vrt layers, and have tried many other ways. The data originally came from two netcdf files. It would be really nice if I could make the layer simply from those two rasters.

Best Answer

OK. After who knows how long, I somewhat got it. I had to write a python program to create a .csv file with Latitude, Longitude, u, and v. After I imported my .csv, I was able to use the vector plugins.

Related Solutions

[GIS] How to Create a Vector Field from Separate u and v Data Files

I wanted to do the same thing, and after some searching found a nice tutorial for how to do this:

http://marine.copernicus.eu/wp-content/uploads/2017/04/1-QGIS_TO_USE_CMEMS_INFORMATION_level2.pdf

[GIS] GDAL Warp to in-memory raster

The best solution for you would be the VSIMEM filesystem which lets you save outputs of gdal utilities into a filesystem stored in memory.

gdal.Warp('/vsimem/reprojected.tif', ds, srcSRS=in_proj, dstSRS=out_proj)

You could also make a vrt:

gdal.Warp('/vsimem/reprojected.vrt', ds, srcSRS=in_proj, dstSRS=out_proj)

Once stored in the vsimem filesystem, the file may be retrieved:

ds = gdal.Open('/vsimem/reprojected.tif')

Files in the vsimem filesystem may also be called as inputs to gdal utilities instead of a local path, which makes it a useful tool when stringing together multiple utility calls while keeping intermediary data in memory.

Use gdal.Unlink('/vsimem/reprojected.tif') to remove from memory.

Best Answer

Related Solutions

[GIS] How to Create a Vector Field from Separate u and v Data Files

[GIS] GDAL Warp to in-memory raster

Related Question