\name{viewEnrichMap}
\alias{viewEnrichMap}
\alias{viewEnrichMap,GSCA-method}
\title{
Plot a figure of the enrichment map for GSEA or Hypergeometric tests
}
\description{
This is a generic function.

When implemented as the S4 method for objects of class \code{\link[HTSanalyzeR:GSCA]{GSCA}}, this function 
will plot an enrichment map for GSEA or Hypergeometric test results.  

To use this function for objects of class \code{\link[HTSanalyzeR:GSCA]{GSCA}}:

viewEnrichMap(object, resultName="GSEA.results", gscs, ntop=NULL, 
allSig=TRUE, gsNameType="id", displayEdgeLabel=TRUE, layout=
"layout.fruchterman.reingold")
}
\usage{
viewEnrichMap(object, ...)
}
\arguments{
	\item{object}{
an object. When this function is implemented as the S4 method of class \code{\link[HTSanalyzeR:GSCA]{GSCA}}, 
this argument is an object of class \code{\link[HTSanalyzeR:GSCA]{GSCA}}.
}
	\item{...}{
other arguments. (see below for the arguments supported by the method of
class \code{\link[HTSanalyzeR:GSCA]{GSCA}})
}
\describe{
	\item{resultName:}{
a single character value: 'HyperGeo.results' or 'GSEA.results'
} 
	\item{gscs:}{
a character vector specifying the names of gene set collections of which
the top significant gene sets will be plotted
}
	\item{ntop:}{
a single integer or numeric value specifying how many gene sets of top 
significance will be plotted.  
}
	\item{allSig:}{
a single logical value. If 'TRUE', all significant gene sets (GSEA
adjusted p-value < 'pValueCutoff' of slot 'para') will be used; otherwise,
only top 'ntop' gene sets will be used.
}
	\item{gsNameType:}{
a single character value specifying the type of the gene set names that 
will be displayed as the names of nodes in the enrichment map. The type of
the gene set names should be one of the following: "id", "term" or "none".
}
	\item{displayEdgeLabel:}{
a single logical value specifying whether or not to display the labels of 
the edges in the enrichment map
}
	\item{layout:}{
a single character value specifying the layout of the enrichment map. 
(see \code{help(layout)} of the package \code{igraph})
}
	\item{plot:}{
a single logical value. If 'TRUE', the enrichment map will be plotted; 
otherwise the function only returns the igraph of enrichment map.
}
}

}
\details{
The idea of this function is similar to the PLoS one paper by Merico et al. 

An enrichment map is a network to help better visualize and interpret the 
GSEA or Hypergeometric test results. In an enrichment map, the nodes 
represent gene sets and the edges denote the Jaccard similarity coefficient 
between two gene sets. Node colors are scaled according to the adjusted 
p-values (the darker the more significant). For GSEA, nodes are colored by 
the sign of the enrichment scores (red:+, blue: -). The size of nodes 
illustrates the size of gene sets, while the width of edges denotes the 
Jaccard coefficient.    
}
\value{
an object of \code{igraph} with all attributes about the enrichement map
}
\seealso{
\code{\link[HTSanalyzeR:plotEnrichMap]{plotEnrichMap}}
}
\references{
Merico, D. et al, Enrichment Map: A Network-Based Method for Gene-Set 
Enrichment Visualization and Interpretation, PloS one, 2010, e13984
}
\author{
Xin Wang \email{xw264@cam.ac.uk}
}

\examples{
\dontrun{
library(org.Dm.eg.db)
library(KEGG.db)
##load data for enrichment analyses
data("KcViab_GSCA")
##plot and save the enrichment map
viewEnrichMap(KcViab_GSCA, gscs=c("GO_MF"), allSig=TRUE, ntop=NULL, gsNameType="id", 
displayEdgeLabel=FALSE,layout="layout.fruchterman.reingold")
##append Gene set terms to results
KcViab_GSCA<-appendGSTerms(KcViab_GSCA, goGSCs=c("GO_BP","GO_MF","GO_CC"), 
keggGSCs=c("PW_KEGG"))
viewEnrichMap(KcViab_GSCA, gscs=c("GO_MF"), allSig=TRUE, ntop=NULL, gsNameType="term", 
displayEdgeLabel=FALSE,layout="layout.fruchterman.reingold")
}
}