Reads the geographic bus locations (longitude and latitude coordinates in degrees) from a CSV file and adds them to the NDD. Returns the resulting NDD, in which each bus has a "bus_lat" and "bus_lon" entry. The columns containg the longitude and latitude coordinates in the CSV file should be called "SubLongitude" and "SubLatitude", respectively.
Builds a network data dictionary conform with PowerModels.jl from several files containing certain input data:
pgfile - .RAW or .m file that contains the detailed grid data (e.g. generator and load information etc.)
busfile - .csv file that contains geographic locations of all buses
branchfile - .csv file that contains transmission line lengths
nddfile - .jld2 file in which the final network data dictionary will be saved
Reads the geographic bus locations (longitude and latitude coordinates in degrees) from a .csv file and adds them to the network data dictionary (NDD). Returns the resulting NDD, in which each bus has a "bus_lat" and "bus_lon" entry. The columns containg the longitude and latitude coordinates in the .csv file should be called "SubLongitude" and "SubLatitude", respectively.
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function add_locs!(network_data::Dict{String,<:Any},csvfile::String)