\name{annotFeaturesWithBiomaRt}
 \alias{annotFeaturesWithBiomaRt}
 \title{Annotation of features using \code{biomaRt}}
 \usage{
   annotFeaturesWithBiomaRt(features, featureId, geneId,
     mart = useMart(biomart = "ensembl", dataset = "hsapiens_gene_ensembl"))
 }
 \arguments{
   \item{features}{Feature IDs to be annotated}
 
   \item{featureId}{The type of the feature IDs, in the
   \code{biomaRt} way (type \code{listFilters(mart)} to
   choose one)}
 
   \item{geneId}{The type of the gene IDs, in the
   \code{biomaRt} way (type \code{listAttributes(mart)} to
   choose one)}
 
   \item{mart}{The mart object (database and dataset) used
   for annotation, see function \code{useMart} of package
   \code{biomaRt}}
 }
 \value{
   A vector of gene IDs indexed by the feature IDs.
 }
 \description{
   This function annotates a set of features using
   \code{biomaRt}
 }
 \examples{
 if (interactive()) {
 # define the database to be queried by biomaRt
 mart <- useMart(biomart="ensembl", dataset="hsapiens_gene_ensembl")
 
 # annotate a set of HG-U133a probe sets IDs into Gene Symbols
 annotFeaturesWithBiomaRt(features = c("1007_s_at", "1053_at", "117_at", "121_at", "1255_g_at"),
 featureId="affy_hg_u133a", geneId="hgnc_symbol", mart=mart)
 
 # annotate a set of Ensembl Gene IDs into Gene Symbols
 annotFeaturesWithBiomaRt(features = c("ENSG00000101412", "ENSG00000112242",
                                       "ENSG00000148773", "ENSG00000131747", "ENSG00000170312",
                                       "ENSG00000117399"), featureId="ensembl_gene_id", geneId="hgnc_symbol", mart=mart)
 }
 }
 \author{
   Anne Biton
 }