gp.open: Alpha version functions to send plotting commands to GnuPlot

In TeachingDemos: Demonstrations for Teaching and Learning

Alpha version functions to send plotting commands to GnuPlot

Description

These functions allow you to open a connection to a gnuplot process, send data and possibly other information to gnuplot for it to plot, then close gnuplot and clean up temporary files and variables. These functions are alpha level at best, use at your own risk.

Usage

gp.open(where='c:/progra~1/GnuPlot/bin/pgnuplot.exe')
gp.close(pipe=gpenv$gp)
gp.send(cmd='replot',pipe=gpenv$gp)
gp.plot(x,y,type='p',add=FALSE, title=deparse(substitute(y)),pipe=gpenv$gp)
gp.splot(x,y,z, add=FALSE, title=deparse(substitute(z)), pipe=gpenv$gp,
  datafile=tempfile())

Arguments

where	Path to GnuPlot Executable
pipe	The pipe object connected to GnuPlot (returned from gp.open), warning: changing this from the default will probably break things
cmd	Text string, the command to be sent verbatim to the GnuPlot process
x	The x coordinates to plot
y	the y coordinates to plot
z	the z coordinates to splot
type	Either 'p' or 'l' for plotting points or lines
add	Logical, should the data be added to the existing plot or start a new plot
title	The title or legend entry
datafile	The file to store the data in for transfer to gnuplot

Details

These functions provide a basic interface to the GnuPlot program (you must have GnuPlot installed (separate install)), gp.open runs GnuPlot and establishes a pipe connection, gp.close sends a quite command to gnuplot and cleans up temporary variables and files, gp.send sends a command to the GnuPlot process verbatim, and gp.plot sends data and commands to the process to create a standard scatterplot or line plot.

Value

gp.open returns and invisible copy of the pipe connection object (to pass to other functions, but don't do this because it doesn't work right yet).

The other 3 functions don't return anything meaningful. All functions are run for their side effects.

Note

These functions create some temporary files and 2 temporary global variables (.gp and .gp.tempfiles), running gp.close will clean these up (so use it).

These functions are still alpha level.

Author(s)

Greg Snow [e-mail]

References

http://www.gnuplot.info/

See Also

plot

Examples

 ## Not run: 

x <- 1:10
y <- 3-2*x+x*x+rnorm(10)

gp.open()
gp.plot(x,y)
gp.send('replot 3-2*x+x**2')

tmp <- expand.grid(x=1:10, y=1:10)
tmp <- transform(tmp, z=(x-5)*(y-3))
gp.splot(tmp$x, tmp$y, tmp$z)

gp.close()
 
## End(Not run)

TeachingDemos documentation built on May 29, 2024, 5:59 a.m.