\name{[-methods} \docType{methods} \alias{[-methods} \title{Methods for "[": Extraction or Subsetting in Package 'Matrix'} % NB: "[<-" are in ./Subassign-methods.Rd % ~~~~~~~~~~~~~~~~~~~~~~ \alias{[,Matrix,missing,missing,ANY-method} \alias{[,Matrix,missing,index,missing-method} \alias{[,Matrix,index,missing,missing-method} \alias{[,Matrix,index,index,missing-method} \alias{[,Matrix,lMatrix,missing,ANY-method} \alias{[,Matrix,logical,missing,ANY-method} \alias{[,Matrix,matrix,missing,ANY-method} \alias{[,Matrix,ANY,ANY,ANY-method}% bail out if no explicit method % \alias{[,denseMatrix,matrix,missing,ANY-method} \alias{[,denseMatrix,index,missing,logical-method} \alias{[,denseMatrix,index,index,logical-method} \alias{[,denseMatrix,missing,index,logical-method} \alias{[,diagonalMatrix,index,missing,logical-method} \alias{[,diagonalMatrix,index,index,logical-method} \alias{[,diagonalMatrix,missing,index,logical-method} % % \alias{[,TsparseTMatrix,missing,missing,ANY-method} \alias{[,TsparseMatrix,index,missing,logical-method} \alias{[,TsparseMatrix,missing,index,logical-method} \alias{[,TsparseMatrix,index,index,logical-method} % \alias{[,sparseMatrix,missing,index,logical-method} \alias{[,sparseMatrix,index,missing,logical-method} \alias{[,sparseMatrix,index,index,logical-method} %------- \description{ Methods for \code{"["}, i.e., extraction or subsetting mostly of matrices, in package \pkg{Matrix}. } \section{Methods}{ There are more than these: \describe{ \item{x = "Matrix", i = "missing", j = "missing", drop= "ANY"}{ ... } \item{x = "Matrix", i = "numeric", j = "missing", drop= "missing"}{ ... } \item{x = "Matrix", i = "missing", j = "numeric", drop= "missing"}{ ... } \item{x = "dsparseMatrix", i = "missing", j = "numeric", drop= "logical"}{ ... } \item{x = "dsparseMatrix", i = "numeric", j = "missing", drop= "logical"}{ ... } \item{x = "dsparseMatrix", i = "numeric", j = "numeric", drop= "logical"}{ ... } } } \seealso{ \code{\link{[<--methods}} for sub\emph{assign}ment to \code{"Matrix"} objects. \code{\link{Extract}} about the standard extraction. } \examples{ % regression tests are in ../tests/indexing.R str(m <- Matrix(round(rnorm(7*4),2), nrow = 7)) stopifnot(identical(m, m[])) m[2, 3] # simple number m[2, 3:4] # simple numeric of length 2 m[2, 3:4, drop=FALSE] # sub matrix of class 'dgeMatrix' ## rows or columns only: m[1,] # first row, as simple numeric vector m[,1:2] # sub matrix of first two columns showMethods("[", inherited = FALSE) } \keyword{methods} \keyword{array}