xGraphML | R Documentation

## Function to generate a graphml file from a graph object of class "igraph"

### Description

`xGraphML` is supposed to generate a graphml file from a graph object of class "igraph".

### Usage

    xGraphML(g, node.label = NULL, label.wrap.width = NULL,
    node.label.size = 12, node.label.color = "#000000", node.tooltip =
    NULL,
    node.link = NULL, node.xcoord = "xcoord", node.ycoord = "ycoord",
    node.color.na = "#dddddd", node.color = NULL,
    colormap = "grey-orange-darkred", ncolors = 64, nlegend = 11,
    legend.label.size = 10, legend.interval = 0.05, zlim = NULL,
    node.size = 30, node.coord.scale = 300, edge.color = "#00000033",
    edge.width = 1, filename = "xGraphML")

### Arguments

`g` | an object of class "igraph"
`node.label` | either a vector labelling nodes or a character specifying which node attribute used for the labelling. If NULL (by default), no node labelling. If provided as a vector, a node with 'NA' will be not labelled
`label.wrap.width` | a positive integer specifying wrap width of name
`node.label.size` | the node label size
`node.label.color` | the node label color
`node.tooltip` | either a vector used for node tooltips or a character specifying which node attribute used for the tooltips. If NULL (by default), node attribute 'name' will be used node lab
`node.link` | a string specifying hyperlink address. By default, it is NULL meaning no hyperlink
`node.xcoord` | a vector specifying x coordinates. If NULL, it will be created using igraph::layout_with_kk
`node.ycoord` | a vector specifying y coordinates. If NULL, it will be created using igraph::layout_with_kk
`node.color.na` | the color for nodes with NA. By default, it is '#dddddd'
`node.color` | a character specifying which node attribute used for node coloring. If NULL (by default), it is '#BFFFBF'

`colormap`

short name for the colormap. It can be one of "jet" (jet colormap), "bwr" (blue-white-red colormap), "gbr" (green-black-red colormap), "wyr" (white-yellow-red colormap), "br" (black-red colormap), "yr" (yellow-red colormap), "wb" (white-black colormap), "rainbow" (rainbow colormap, that is, red-yellow-green-cyan-blue-magenta), and "ggplot2" (emulating ggplot2 default color palette). Alternatively, any hyphen-separated HTML color names, e.g. "lightyellow-orange" (by default), "blue-black-yellow", "royalblue-white-sandybrown", "darkgreen-white-darkviolet". A list of standard color names can be found in http://html-color-codes.info/color-names

`ncolors` | the number of colors specified over the colormap
`nlegend` | the number of colors specified in the legend. By default, it is 11
`legend.label.size` | the legend label size. By default, it is 10
`legend.interval` | the interval between legends. By default, it is 0.05
`zlim` | the minimum and maximum z/patttern values for which colors should be plotted, defaulting to the range of the finite values of z. Each of the given colors will be used to color an equispaced interval of this range. The midpoints of the intervals cover the range, so that values just outside the range will be plotted
`node.size` | either a vector specifying node size or a character specifying which node attribute used for the node size. If NULL (by default), it will be 30
`node.coord.scale` | the node coord (-1,1) subjected to be rescaled. By default, it is 300
`edge.color` | a character specifying the edge colors. By default, it is #00000033
`edge.width` | the edge width. By default, it is 1
`filename` | the without-extension part of the name of the output file. By default, it is 'xGraphML'

### Value

invisible (a string storing graphml-formatted content). If the filename is not NULL, a graphml-formatted file is also output.

### Note

none

### See Also

`xGraphML`

### Examples

    ## Not run:
    # Load the library
    library(XGR)
    RData.location <- "http://galahad.well.ox.ac.uk/bigdata/"

    # 1) load REACTOME
    # 1a) restricted to Immune System ('R-HSA-168256') or Signal Transduction ('R-HSA-162582')
    g <- xRDataLoader(RData.customised='ig.REACTOME',
    RData.location=RData.location)
    neighs.out <- igraph::neighborhood(g, order=vcount(g),
    nodes="R-HSA-168256", mode="out")
    nodeInduced <- V(g)[unique(unlist(neighs.out))]$name
    ig <- igraph::induced.subgraph(g, vids=nodeInduced)
    # visualise the graph with vertices being color-coded by the pattern
    V(ig)$pattern <- runif(vcount(ig))
    xGraphML(g=ig, node.label="name", node.color="pattern", colormap="wyr",
    node.size=10, node.label.size=6)

    # 1b) restricted to Signal Transduction ('R-HSA-162582')
    g <- xRDataLoader(RData.customised='ig.REACTOME',
    RData.location=RData.location)
    neighs.out <- igraph::neighborhood(g, order=vcount(g),
    nodes="R-HSA-162582", mode="out")
    nodeInduced <- V(g)[unique(unlist(neighs.out))]$name
    ig <- igraph::induced.subgraph(g, vids=nodeInduced)
    # visualise the graph with vertices being color-coded by the pattern
    V(ig)$pattern <- runif(vcount(ig))
    xGraphML(g=ig, node.label="name", node.color="pattern", colormap="wyr",
    node.size=8, node.label.size=4)

    ###########################
    # visualise gene network
    glayout <- igraph::layout_with_kk(ig)
    V(ig)$xcoord <- glayout[,1]
    V(ig)$ycoord <- glayout[,2]
    xGraphML(g=ig, node.label="name", node.tooltip="description",
    node.xcoord="xcoord", node.ycoord="ycoord", node.color="pattern",
    colormap="grey-orange-darkred",
    node.link="http://www.genecards.org/cgi-bin/carddisp.pl?gene=",
    nlegend=11, node.size=30, node.coord.scale=300)

    ## End(Not run)