IceCast (version 2.1.0)

reg_info: List of information about each region

Description

A region information list, reg_info, is a list of ten items regions,start_lines, start_lines_coords, start_coords, end_coords, out, lines, dist, loop, and angs. The package contains a reg_info object which is typically what is used for all analyses. However, it would be possible to redefine the regions if desired by making a new reg_info object.

Usage

reg_info

Format

An object of class list of length 10.

Details

regions: list of SpatialPolygons objects corresponding to each region.

start_lines: list of SpatialLines object giving the line from which each mapping or contour generation will start. For the central Arctic region, a single SpatialPoint is used instead. List ordered the same as reg_info$regions

start_lines_coords: list of matrices giving the coordinates that approximately match reg_info$start_lines, except that they extend to touch the end point of the first and last fixed line. For the central Arctic region, the coordinate of the start_lineis just repeated. List ordered the same as reg_info$regions

start_coords: list of matrices giving the coordinates from which the lines start. List ordered the same as reg_info$regions

end_coords: list of matrices giving the coordinates between the end points of the first and last fixed line. List ordered the same as reg_info$regions

out: list of SpatialPolygons object that border reg_info$start_lines, but are outside the region. These are used when building new polygons to determine if points are outside the region of interest. List ordered the same as reg_info$regions

lines: list giving the SpatialLines objects that correspond to the line on which contours are mapped and built.

dist: list for each region with one item for each line reg_info$lines giving the lengths at which restrictions on the line lengths occur. The first element for all entries is 0 and the last element is the length of the line. Elements in between refer to the starting and ending lengths on which points cannot be placed. The first list index is ordered the same as reg_info$regions and the second list index is ordered as the corresponding lines in reg_info$lines

loop: vector gives a Boolean for each region. The value TRUE indicates that the lines are mapped in a circle around a fixed point. The value FALSE indicates that the lines are mapped along a line on land. The first element, corresponding to the central Arctic region is TRUE. All others are FALSE. Elements ordered the same as reg_info$regions

angs: list of vectors giving the angles of the corresponding reg_info$lines. Elements ordered the same as reg_info$regions

References

The regions in this object have been substantially modified from the following region mask:

National Snow and Ice Data Center, 2017: Region mask for the northern hemisphere http://nsidc.org/data/polar-stereo/tools_masks.html.

Examples

# NOT RUN {
data(reg_info)
names(reg_info)
# }