lab2: Lab 2

In zalmquist/networkMethods: Network Methods

Description

lab2 returns simple description of the first lab in Soc 88412.

Usage

lab2()

Arguments

Empty

Details

This is a simple description of the lab, use help(lab1) to review the examples for this lab

Examples

library(sna)                      # Load the sna library
data(contig_1993)
data(mids_1993)

#-Network visualization with gplot----------------------------------------------
#
# Begin by plotting contiguity among nations in 1993 (from the Correlates of
# War project)
gplot(contig_1993)                              # The default visualization
gplot(contig_1993, usearrows=FALSE)             # Turn off arrows manually
gplot(contig_1993, gmode="graph")               # Can also tell gplot the data
# is undirected

# We can add labels to the vertices - network.vertex.names reports them
gplot(contig_1993, gmode="graph", label=network.vertex.names(contig_1993))
# This plot is too large/dense for the default settings to work.  Let's refine
# them.
gplot(contig_1993, gmode="graph", boxed.labels=FALSE, label.cex=0.5,
      label.col=4, label=network.vertex.names(contig_1993)) # Shrink labels,
# remove boxes, recolor

# Here's an example of directed data - militarized interstate disputes (MIDs)
# for 1993
gplot(mids_1993, boxed.labels=FALSE, label.cex=0.5, label.col=4,
      label=network.vertex.names(mids_1993))       # Basic display, with labels

# All those isolates can get in the way - we can suppress them using
# displayisolates
gplot(mids_1993, displayisolates=FALSE, boxed.labels=FALSE, label.cex=0.5,
      label.col=4,label=network.vertex.names(mids_1993))

# The default layout algorithm is that of Frutchterman-Reingold (1991), can use
# others
gplot(mids_1993, displayisolates=FALSE, boxed.labels=FALSE, label.cex=0.5,
      label.col=4,label=network.vertex.names(mids_1993),
      mode="circle")   # The infamous circle
gplot(mids_1993, displayisolates=FALSE, boxed.labels=FALSE, label.cex=0.5,
      label.col=4,label=network.vertex.names(mids_1993),
      mode="mds")      # MDS of position similarity

# When a layout is generated, the results can be saved for later reuse:
coords <- gplot(contig_1993)                  # Capture the magic of the moment
coords                                        # Show the vertex coordinates

#Saved (or a priori) layouts can be used via the coord argument:
gplot(mids_1993, boxed.labels=FALSE, label.cex=0.5, label.col=4, coord=coords,
      label=network.vertex.names(mids_1993))        # Relive the magic

# When the default settings are insufficient, interactive mode allows for
# tweaking
coords <- gplot(contig_1993, interactive=TRUE)   # Modify and save
gplot(contig_1993, coord=coords, gmode="graph")  # Should reproduce the modified
# layout
## Not run: 
#
#Three-dimensional visualization with gplot3d (requires the rgl package)--------
# Note that this requires X11

# Note: if you haven't done so, you can install the rgl package by typing
# install.packages("rgl") at the command prompt (assuming you are online).
# If that package is not installed, you'll get a boring error message instead
# of exciting visualization.

gplot3d(contig_1993, label=network.vertex.names(contig_1993))   # Experience
# the future!
# Other layouts are possible here, too:
gplot3d(contig_1993, label=network.vertex.names(contig_1993),mode="kamadakawai")

#For more information....
?gplot
?gplot.layout

#For more information....
?gplot3d
?gplot3d.layout

## End(Not run)

zalmquist/networkMethods documentation built on May 4, 2019, 9:08 p.m.