cat.to.list.R
# fields is a package for analysis of spatial data written for
# the R software environment .
# Copyright (C) 2017
# University Corporation for Atmospheric Research (UCAR)
# Contact: Douglas Nychka, nychka@ucar.edu,
# National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with the R software environment if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
# or see http://www.r-project.org/Licenses/GPL-2
"cat.to.list" <- function(x, a) {
a <- as.character(a)
label <- unique(a)
out <- as.list(1:length(label))
names(out) <- label
for (k in 1:length(label)) {
out[[k]] <- x[label[k] == a]
if (length(out[[k]]) == 0)
out[[k]] <- NA
}
out
}