nightlight_calculate: nightlight_calculate
In mark-toth-econ/nightlightstats: nightlightstats

Description Usage Arguments

View source: R/nightlight_calculate.R

Perform calculations on nightlights of a region in a given time inteval (defaults are sum of light values, min and max).

nightlight_calculate(
area_names,
time_from,
time_to,
light_location,
output_location = ".",
admlevel = 0,
shapefiles = NULL,
download_shape = "sp.rds",
functions_calculate = NULL,
function_names = NULL,
rectangle_calculate = FALSE,
rawdata = FALSE,
cut_low = NULL,
cut_high = NULL,
xmin = NULL,
xmax = NULL,
ymin = NULL,
ymax = NULL)

`area_names`	May not be empty. String (vector) with the name(s) of your region(s). If you provide a country name, the country shapefile will be downloaded automatically, except if it is already in your working directory. If you provide own shapefiles in the shapefiles argument, put the names in order of the shapefile order. If you only put one name for multiple shapefiles, all shapefiles will be processed with that name.
`time_from`	May not be empty. String with the starting date in the format "2012-04". The monthly data goes from Apr 2012 onwards. If this is a year, then simply "1992". The yearly data goes from 1992 to 2013.
`time_to`	May not be empty. String with the end date in the format "2012-04". The monthly data goes from Apr 2012 onwards. If this is a year, then simply "1992". The yearly data goes from 1992 to 2013. If only one time period is desired, then time_from = time_to.
`light_location`	May not be empty. Provide the location of the lightfiles on your drives as a string. Yearly data all have to be in one folder, monthly data in folders "tileX", X being a tilenumber. For monthly data, provide the path to these "tileX" folders.
`output_location`	Default is the working directory. Will output files here.
`admlevel`	Default is 0. Change this when working with different administrative levels. Important for nightlight_calculate: if your shapefile is not from GADM and features admlevels larger than 0, you must rename the column names to NAME_X, X being the admlevel. You can do this by reading the shapefile e.g. with readRDS or rgdal::readOGR, renaming the columns of the SpatialPolygonsDataFrame accordingly and then saving the shapefile again. Only with this naming will the calculation with lower admlevels work if the shapefile is not from GADM.
`shapefiles`	May be empty. You can provide own shapefiles here if no automatic download is desired. If there is a shapefile in your working directory that has either the name of the region which you enter in area_names or the ISO3 of the country (if it is a country) in its filename, it will be detected automatically and you do not have to use this argument.
`download_shape`	Default is "sp.rds". Change to ".shp", ".kml" or ".gpkg" if you want to download a different shapefile format from GADM. Will only download if no own shapefiles are provided in the shapefiles argument or present in the working directory.
`functions_calculate`	Defaults (activated if this is NULL) are sum of lights, min and max. These calculations will be performed on the night light data for your given time and region. Functions need to support the possibility to set na.rm as an argument. See the documentation of raster::extent, into which I feed the functions, for further details when encountering problems. The functions have to be given in a vector, even if there is only one function.
`function_names`	Defaults (activated if this is NULL) are lightsum, lightmin and lightmax. This is a vector of strings and gives names to the columnns in the final dataframe output for each calculation you perform.
`rectangle_calculate`	Default is FALSE. If your shapefile does not allow calculating values within its borders (always possible for GADM shapefiles), you should set this to true. The code will calculate the values for the smallest rectangle that reaches over the full extent of the shapefile. If you are not sure whether this applies for you, you can check whether your shapefile encloses a well-defined area by plotting it.
`rawdata`	Default is FALSE. If set to TRUE, an additional file with the raw night light data, i.e. the light values and their coordinates, will be produced for each time period.
`cut_low`	May be empty. If a value is provided, light values below cut_low will be set to NA before performing calculations.
`cut_high`	May be empty. If a value is provided, light values above cut_high will be set to NA before performing calculations.
`xmin`	May be empty. Decimal number (longlat). Can be specified if you want to calculate for a region defined by specific coordinates.
`xmax`	May be empty. Decimal number (longlat). Can be specified if you want to calculate for a region defined by specific coordinates.
`ymin`	May be empty. Decimal number (longlat). Can be specified if you want to calculate for a region defined by specific coordinates.
`ymax`	May be empty. Decimal number (longlat). CCan be specified if you want to calculate for a region defined by specific coordinates.