R/vect_link.R

In rsbivand/rgrass7: Interface Between 'GRASS' Geographical Information System and 'R'

# Interpreted GRASS interface functions
# Copyright (c) 2015-22 Roger S. Bivand
#


vInfo <- function(vname, layer, ignore.stderr = NULL) {
        if (get.suppressEchoCmdInFuncOption()) {
            inEchoCmd <- get.echoCmdOption()
             tull <- set.echoCmdOption(FALSE)
        }
        if (is.null(ignore.stderr))
            ignore.stderr <- get("ignore.stderr", envir = .GRASS_CACHE)
        stopifnot(is.logical(ignore.stderr))

        if (missing(layer)) layer <- "1"
        layer <- as.character(layer)
	vinfo0 <- execGRASS("v.info", flags="t", map=vname,
            layer=layer, intern=TRUE, ignore.stderr=ignore.stderr)

# fix to avoid locale problems 091022

        vinfo1 <- gsub("=", ":", vinfo0)
	con <- textConnection(vinfo1)
	res <- drop(read.dcf(con))
	close(con)
        if (get.suppressEchoCmdInFuncOption()) {
            tull <- set.echoCmdOption(inEchoCmd)
        }
	storage.mode(res) <- "integer"
	res
}

vColumns <- function(vname, layer, ignore.stderr = NULL) {
        if (get.suppressEchoCmdInFuncOption()) {
            inEchoCmd <- get.echoCmdOption()
             tull <- set.echoCmdOption(FALSE)
        }
        if (is.null(ignore.stderr))
            ignore.stderr <- get("ignore.stderr", envir = .GRASS_CACHE)
        stopifnot(is.logical(ignore.stderr))
        if (missing(layer)) layer <- "1"
        layer <- as.character(layer)
	vinfo0 <- execGRASS("v.info", flags="c", map=vname,
            layer=layer, intern=TRUE, ignore.stderr=ignore.stderr)       
        vinfo1 <- strsplit(vinfo0, "\\|")
        vinfo2 <- vinfo1[sapply(vinfo1, length) == 2]
        if (length(vinfo1) != length(vinfo2))
            warning("vColumns: v.info -c output not in two columns:\n",
                paste(vinfo1[sapply(vinfo1, length) != 2]))
        res <- as.data.frame(do.call("rbind", vinfo2))
	names(res) <- c("storageType", "name")
        if (get.suppressEchoCmdInFuncOption()) {
            tull <- set.echoCmdOption(inEchoCmd)
        }
	res
}

vDataCount <- function(vname, layer, ignore.stderr = NULL) {
        if (get.suppressEchoCmdInFuncOption()) {
            inEchoCmd <- get.echoCmdOption()
             tull <- set.echoCmdOption(FALSE)
        }
        if (is.null(ignore.stderr))
            ignore.stderr <- get("ignore.stderr", envir = .GRASS_CACHE)
        stopifnot(is.logical(ignore.stderr))
        column <- "column" %in% parseGRASS("v.db.select")$pnames
        if (missing(layer)) layer <- "1"
        layer <- as.character(layer)
        parms <- list(map=vname, layer=as.character(layer), columns="cat")
        if (column) tull <- execGRASS("v.db.select", flags="c",
            parameters=parms, intern=TRUE, ignore.stderr=ignore.stderr)
        else tull <- execGRASS("v.db.select", flags="c",
            parameters=parms, intern=TRUE, ignore.stderr=ignore.stderr)
	n <- length(tull)
        if (get.suppressEchoCmdInFuncOption()) {
            tull <- set.echoCmdOption(inEchoCmd)
        }
	n
}


#Date: Thu, 13 Oct 2005 17:34:06 +0200
#From: Markus Neteler <neteler@itc.it>
#
#EXERCISE: HOW LONG ARE COMMON BOUNDARIES OF POLYGONS?
#
#
## Requires: GRASS 6.1-CVS from 13 Oct 2005 or later
##
## data: sudden infant deaths data from North Carolina
## data imported from SHAPE file with v.in.ogr
#
##let's have a look
# d.mon x0
# d.vect sids
#
##we work on a copy:
# g.copy vect=sids,sids_nc
#
##we add a second layer to the map which references the boundaries of
##polygons. In the vector geometry we generate an ID (category) for each
##boundary:
# v.category sids_nc out=sids_nc2 layer=2 type=boundary option=add
#
##Underlying idea:
##we'll fetch the IDs (categories) of the polygons left and right from
##each boundary and store it into the attribute table linked to layer 2.
##In general:
## cat_of_boundary | cat_of_left_polygon | cat_of_right_polygon | length_of_boundary
##
##We want only one category per boundary, that's why the sides check is
##needed (a boundary may consist of several pieces)
##
##So we create a new attribute table and link it to the new layer 2
##of the vector map:
# v.db.addtable sids_nc2 layer=2 col="left integer,right integer,length integer"
#
##Now we query the polygon/boundary relationsships and store it into
##the attribute table linked to layer 2:
# v.to.db map=sids_nc2 option=sides col=left,right layer=2 
#
##Now we have unique categories for the boundaries and can calculate the
##lengths:
# v.to.db map=sids_nc2 option=length col=length layer=2 
#
##Done.
#
##See the new attribute table containing the boundary lengths:
# v.db.select sids_nc2 layer=2
#
## verification (let's check boundary #193):
# d.vect sids_nc2 cat=193 layer=2 col=red type=boundary
# d.zoom
# d.measure
## LEN:     12756.00 meters
#
##what does the attribute table say:
# v.db.select sids_nc2 layer=2 | grep '^193'
##190|65|68|12814
#
##This is reasonably close since on screen digitization in d.measure
##isn't always that precise ...
#

vect2neigh <- function(vname, ID=NULL, ignore.stderr = NULL, remove=TRUE,
    vname2=NULL, units="k") {

    if (get.suppressEchoCmdInFuncOption()) {
        inEchoCmd <- get.echoCmdOption()
        tull <- set.echoCmdOption(FALSE)
    }
    if (is.null(ignore.stderr))
        ignore.stderr <- get("ignore.stderr", envir = .GRASS_CACHE)
    stopifnot(is.logical(ignore.stderr))

    vinfo <- vInfo(vname)
    types <- names(vinfo)[which(vinfo > 0)]
    if (length(grep("areas", types)) == 0) 
		stop("Vector object not of area type")

    n <- vDataCount(vname, ignore.stderr=ignore.stderr)


    if (!is.null(ID)) {
		if (!is.character(ID)) stop("ID not character string")
#		cmd <- paste(paste("v.info", .addexe(), sep=""),
#                    " -c ", vname, sep="")
#		if(.Platform$OS.type == "windows") 
#			tull <- system(cmd, intern=TRUE)
#		else tull <- system(cmd, intern=TRUE, 
#			ignore.stderr=ignore.stderr)
                tull <- execGRASS("v.info", flags="c",
                        map=vname, intern=TRUE, 
			ignore.stderr=ignore.stderr)
		if (length(grep(ID, tull)) == 0)
			stop("ID not found")
#		cmd <- paste(paste("v.db.select", .addexe(), sep=""),
#                    " -c map=", vname, " column=", 
#			ID, sep="")
#		if(.Platform$OS.type == "windows") 
#			ID <- as.character(system(cmd, intern=TRUE))
#		else ID <- as.character(system(cmd, intern=TRUE, 
#			ignore.stderr=ignore.stderr))
                ID <- execGRASS("v.db.select", flags="c", 
                        map=vname, columns=ID, intern=TRUE, 
			ignore.stderr=ignore.stderr) 
		if (length(unique(ID)) != n) 
			stop("fewer than n unique ID values")
    }
    vname2_was_null <- FALSE
    if (is.null(vname2)) {
	
	pid <- as.integer(round(runif(1, 1, 1000)))
	vname2 <- paste(vname, pid, sep="")
        tull <- execGRASS("g.remove", type="vector", name=vname2, flags="f",
            intern=TRUE, ignore.stderr=ignore.stderr)
#	cmd <- paste(paste("g.copy", .addexe(), sep=""),
#                    " vect=", vname, ",", vname2, sep="")
#	if(.Platform$OS.type == "windows") tull <- system(cmd, intern=TRUE)
#	else tull <- system(cmd, intern=TRUE, ignore.stderr=ignore.stderr)
        tull <- execGRASS("g.copy", vector=paste(vname, 
            vname2, sep=","), flags="overwrite", intern=TRUE,
            ignore.stderr=ignore.stderr)
        vname2_was_null <- TRUE
    }
    vname2a <- paste(vname2, "a", sep="")
    if (vname2_was_null) {
#	cmd <- paste(paste("v.category", .addexe(), sep=""),
#                    " ", vname2, " out=", vname2a, 
#		"  layer=2 type=boundary option=add", sep="")
#	if(.Platform$OS.type == "windows") tull <- system(cmd, intern=TRUE)
#	else tull <- system(cmd, intern=TRUE, ignore.stderr=ignore.stderr)
        tull <- execGRASS("v.category", input=vname2,
                output=vname2a, layer=as.character(2), type="boundary",
                option="add", flags="overwrite", intern=TRUE, ignore.stderr=ignore.stderr)

#	cmd <- paste(paste("v.db.addtable", .addexe(), sep=""),
#                    " ", vname2a, 
#	" layer=2 col=\"left integer,right integer,length double precision\"", 
#	sep="")
#	if(.Platform$OS.type == "windows") system(cmd)
#	else system(cmd, ignore.stderr=ignore.stderr)
        execGRASS("v.db.addtable", map=vname2a, 
                layer=as.integer(2),
                columns="left integer,right integer,length double precision",
                ignore.stderr=ignore.stderr)

# Using vector map name extended by layer number as table name: landuse175a_2
#Creating table with columns (cat integer, left integer,right integer,length
# double precision)
# The table <landuse175a_2> is now part of vector map <landuse175a> and may
# be deleted or overwritten by GRASS modules
# Select privileges were granted on the table
# Reading features...
# 
# and: no such driver available
# WARNING: Unable to start driver <and>
# ERROR: Unable to open database <C:\Documents> by driver <and>
# Current attribute table links:
# layer <1> table <landuse175a> in database <C:\Documents and Settings\s1155\My Documents\GIS DataBase/Spearfish60/s1155/dbf/> through driver <dbf> with key <cat>
# layer <2> table <landuse175a_2> in database <C:\Documents> through driver <and> with key <cat>
# Vector map <landuse175a@s1155> is connected by:


#	cmd <- paste(paste("v.to.db", .addexe(), sep=""),
#                    " map=", vname2a, 
#		" option=sides col=left,right layer=2", sep="")
#	if(.Platform$OS.type == "windows") system(cmd)
#	else system(cmd, ignore.stderr=ignore.stderr)
        execGRASS("v.to.db", flags=c("overwrite"), map=vname2a, option="sides",
                columns="left,right", layer=as.character(2),
                ignore.stderr=ignore.stderr)

#	cmd <- paste(paste("v.to.db", .addexe(), sep=""),
#                    " map=", vname2a, 
#		" option=length col=length layer=2", sep="")
#	if(.Platform$OS.type == "windows") system(cmd)
#	else system(cmd, ignore.stderr=ignore.stderr)
        execGRASS("v.to.db", flags=c("overwrite"), map=vname2a, option="length",
                columns="length", layer=as.character(2), units=units,
                ignore.stderr=ignore.stderr)

#	cmd <- paste(paste("v.db.select", .addexe(), sep=""),
#                    " ", vname2a, " layer=2", sep="")
#
#	if(.Platform$OS.type == "windows") res <- system(cmd, intern=TRUE)
#	else res <- system(cmd, intern=TRUE, ignore.stderr=ignore.stderr)
    }
    res <- execGRASS("v.db.select", map=vname2a,
          layer=as.character(2), flags="overwrite", intern=TRUE,
          ignore.stderr=ignore.stderr)

#	cmd <- paste(paste("g.remove", .addexe(), sep=""),
#                    " vect=", vname2, ",", vname2a, sep="")
#	if(.Platform$OS.type == "windows") tull <- system(cmd, intern=TRUE)
#	else tull <- system(cmd, intern=TRUE, ignore.stderr=ignore.stderr)
    if (remove) tull <- execGRASS("g.remove",
            name=paste(vname2, vname2a, sep=","), type="vector",
            intern=TRUE, ignore.stderr=ignore.stderr)

    con <- textConnection(res)
    t2 <- read.table(con, sep="|", header=TRUE, row.names=1)
    close(con)
    t3 <- t2[t2$left == -1,]
    t4 <- tapply(t3$length, t3$right, sum)
    external <- numeric(n)
    external[as.integer(names(t4))] <- t4
    t5 <- t2[!t2$left == -1,]
    tmp <- t5$left
    t5$left <- t5$right
    t5$right <- tmp
    t6 <- rbind(t2, t5)
    total <- c(tapply(t6$length, t6$right, sum))
    res <- t6[!t6$left == -1,]
#       avoid integer overflow in by=
#	res <- aggregate(res[3], by=list(left=res$left, right=res$right), sum)
#        dups <- duplicated(res[,1:2])
#        resd <- res[dups,]
#        resda <- aggregate(resd[3], by=list(left=resd$left,
#            right=resd$right), sum)
#        resnd <- res[!dups,]
#        res <- rbind(resda, resnd)
    zz <- paste(res$left, res$right, sep=":")
    uzz <- unique(zz)
    mo <- match(zz, uzz)
    smo <- c(tapply(res[,3], mo, sum))
    names(smo) <- NULL
    suzz <- strsplit(uzz, ":")
    lsuzz <- as.integer(sapply(suzz, "[", 1))
    rsuzz <- as.integer(sapply(suzz, "[", 2))
    reso <- data.frame(left=lsuzz, right=rsuzz, length=smo)
    o <- order(reso$left, reso$right)
    reso <- reso[o,]
    attr(reso, "external") <- external
    attr(reso, "total") <- total
    attr(reso, "region.id") <- ID
    attr(reso, "n") <- n
    class(reso) <- c(class(reso), "GRASSneigh", "spatial.neighbour")
    if (get.suppressEchoCmdInFuncOption()) {
        tull <- set.echoCmdOption(inEchoCmd)
    }

    reso
}