# $Id: CDFgetdata,v 1.8 1993/08/26 19:47:44 mintha Exp $
#
# Get the data for a specified variable
# Given the global structure and varid
#
# $Log: CDFgetdata,v $
# Revision 1.8  1993/08/26  19:47:44  mintha
# Fixes dnames attribute to be a character vector not a list
#
# Revision 1.7  1993/08/26  19:22:09  mintha
# Added dnames attribute to variable (Dimension names)
#
# Revision 1.6  1993/08/26  10:11:27  mintha
# Better error checking for invalid var names
#
# Revision 1.5  1993/08/25  21:34:58  mintha
# Splus parse seems to have strange behavior, calling C routine to parse strings.
#
# Revision 1.4  1993/08/19  00:52:00  mintha
# Further fixed dim names lengths.  If the number of labels is not
# equal to the length of that dimension then NULL even if we are
# only taking a hyperslab which there are labels for.
#
# Revision 1.3  1993/08/19  00:39:20  mintha
# Only add dim labels if there is a label for each element otherwise NULL
#
# Revision 1.2  1993/08/13  22:23:07  mintha
# Added "-1" parameter which is replaced by the remaining length for
# the count.  (startdims & slicedims replaced by start & count)
#
# Revision 1.1  1993/08/10  23:28:20  mintha
# Initial revision
#
"CDFgetdata" <-
function(info, var, start=NULL, count=NULL)
{
	if(is.character(var)) var <- match(var, names(info), nomatch=-1)-2

	if(var < 0 || var > info$global$numvars)
		stop("Variable specified does not exist\n");

	varinfo <- info[[var+2]]
#
# Get the Data
#
	if(is.null(start))
		start <- rep(1, length(varinfo$dims))
	if(is.null(count))
		count <- rep(-1, length(varinfo$dims))
#
# Any parameter not given for count will be set to the rest of the array.
#
	for(ctr in seq(to = length(varinfo$dims))){
		if(count[ctr] == -1)
			count[ctr] <- varinfo$dims[ctr] - start[ctr] + 1
	}
	datasize <- prod(count)
	type <- varinfo$type

	data <- .C("cdf_read_data",
		as.integer(info$global$ncid),
		as.integer(var),
		as.integer(type),
		as.integer(rev(start-1)),
		as.integer(rev(count)),
		cdata = character(datasize),
		fdata = single(datasize),
		ddata = double(datasize))

	if(type == 2) vdata <- array(data$cdata, dim=count)
	if(type == 5) vdata <- array(data$fdata, dim=count)
	if(type == 6) vdata <- array(data$ddata, dim=count)

	dlabels <- vector("list", length(varinfo$dims))
	dnames <- character(length(varinfo$dims))

	for(ctr in seq(to = length(varinfo$dims))){
		dnames[ctr] <- info$global$dnames[varinfo$dimids[ctr]+1]
		if(varinfo$labels[ctr] != "NULL"){
			temp <- .C("parse_string",
				as.character(varinfo$labels[ctr]),
				strs=character(0),
				pointers=c(F,T))
			if(length(temp$strs) == varinfo$dims[ctr])
				dlabels[[ctr]] <- temp$strs[(start[ctr]):(start[ctr]+count[ctr]-1)]
		}
	}
	attr(vdata, "dnames") <- dnames
	if(length(varinfo$dims) > 1)
		dimnames(vdata) <- dlabels
	else
		names(vdata) <- dlabels[[1]]
# 
# Other attibutes
#
	if(length(varinfo) > 5){
		for(ctr in seq(from=6, to=length(varinfo)))
			attr(vdata, names(varinfo)[[ctr]]) <- varinfo[[ctr]]
	}
	vdata
}