irsarea {spsurvey} | R Documentation |
This function selects an independent random sample (IRS) of an area resource.
irsarea(shapefilename=NULL, areaframe, samplesize=100, SiteBegin=1, maxtry=1000)
shapefilename |
name of the input shapefile. If shapefilename equals NULL, then the shapefile or shapefiles in the working directory are used. The default is NULL. |
areaframe |
a data frame containing id, mdcaty and mdm. |
samplesize |
number of points to select in the sample. The default is 100. |
SiteBegin |
number to use for first site in the design. The default is 1. |
maxtry |
maximum number of iterations for randomly generating a point within the frame to select a site when type.frame equals "area". The default is 1000. |
A data frame of IRS sample points containing: SiteID, id, x, y, mdcaty, and weight.
Tom Kincaid Kincaid.Tom@epa.gov