addTable() adds an entire table to a GVector. It will replace any existing table. There must be one row in the table for each geometry (see ngeom()). You can also add a table column-by-column using the $<- operator.
dropTable() removes a data table associated with a GVector.
Usage
# S4 method for class 'GVector,data.frame'
addTable(x, ...) <- value
# S4 method for class 'GVector,data.table'
addTable(x, ...) <- value
# S4 method for class 'GVector,matrix'
addTable(x, ...) <- value
# S4 method for class 'GVector'
dropTable(x)Examples
if (grassStarted()) {
# Setup
library(sf)
# Rivers vector
madRivers <- fastData("madRivers")
# Convert sf to a GVector
rivers <- fast(madRivers)
# Convert GVector to data.frame or data.table
as.data.frame(rivers)
as.data.table(rivers)
# Subset rivers vector
rivers1 <- rivers[1:2]
rivers2 <- rivers[10:11]
# Concatenate rivers
riversCombo <- rbind(rivers1, rivers2)
riversCombo
# Add columns
newCol <- data.frame(new = 1:11)
riversCol <- colbind(rivers, newCol)
riversCol
# Remove table
riversCopy <- rivers
riversCopy # has data table
riversCopy <- dropTable(riversCopy)
riversCopy # no data table
# Add a new table
newTable <- data.frame(num = 1:11, letters = letters[1:11])
addTable(riversCopy) <- newTable
riversCopy
}