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ggplot2 opts list https github com hadley ggplot2…

leur site web ggplot2 opts list

https://github.com/hadley/ggplot2/wiki/%2Bopts%28%29-List

June 15, 2012

Sometimes R gives the error message Error in…

Sometimes R gives the error message.

Error in X11(d$display, d$width, d$height, d$pointsize, d$gamma, d$colortype,  : 
  unable to start device X11cairo

Here is the fix.

Sys.setenv("DISPLAY"=":0.0")

June 15, 2012

Display file contents with file names tail +1…
Display file contents with file names;
```
tail +1 many_files*
```
It works on Mac, BSD.

For GNU tail, use
```
tail -n +1 many_files*
```
Update: GNU tail has different parameters.

http://stackoverflow.com/questions/5917413/cat-multiple-files-but-include-filename-as-headers
June 6, 2012
Two ways to save a plot in png…
Two ways to save a plot in png.

dev.copy() saves the plot with transparent background while savePlot() with white background.
See the difference.
```
dev.copy(device = png, file = "devcopy.png")
dev.off()
```
```
savePlot(file = "saveplot.png")
```
Saved by dev.copy()
Saved by savePlot()
May 31, 2012
Using discontinuous axis or breaks may not…

Using discontinuous axis or “breaks” may not be a good idea to visualize data.
Instead, use two plots, one with the whole data and another for zoomed data.
However, if the situation is not allowed, there is an R package to do it.
The package plotrix can put breaks or gaps on the axes.

May 31, 2012

How to use eval Here is an example…

How to use eval()?
Here is an example.

test.dframe <- data.frame(x = 1:10, y = rnorm(10))                                                                                                                                
addSmooth <- function(data, smooth = TRUE) {
    require(ggplot2)
    p <- "ggplot(data = data, aes(x = x, y = y))"
    p.line <- "geom_line()"
    p.smooth <- "stat_smooth()"
    if (smooth == TRUE) {
        p.all <- paste(p, p.line, p.smooth, sep = " + ")
    } else {
        p.all <- paste(p, p.line, sep = " + ")
    }.
    eval(parse(text = p.all))
}
 
addSmooth(test.dframe, smooth = FALSE)

Created by Pretty R at inside-R.org

May 30, 2012

checkUsage in the codetools package examines the function…

checkUsage() in the codetools package examines the function and report possible problems.

R functions look for a global variable if the variable is not found in the scope. If a function accidentally has an “orphan” variable which is not passed on to the function but has the same name as one of the global variables, the function will use the value of the global variable. It is a hard to find bug. checkUsage() will find such cases and report.

May 24, 2012

Multiple plots with different titles using ggplot lapply…

Multiple plots with different titles using ggplot, lapply, and do.call.

parameters = data.frame(p1=letters[1:5], p2=round(rnorm(5),2))
l = replicate(5, data.frame(x=1:10, y=rnorm(10)), simplify=FALSE)
names(l) = do.call(paste, c(parameters, sep=","))
 
plot_one = function(x)
  ggplot(data = l[[x]]) + geom_path(aes(x, y)) +
   opts(title = x)
 
plots = lapply(names(l), plot_one)
 
do.call(gridExtra::grid.arrange, plots)

Created by Pretty R at inside-R.org

http://stackoverflow.com/questions/10726470/ggplot-over-many-data-frames-changing-titles

May 24, 2012

Defining Macros on the Command Line Macros can…

Defining Macros on the Command Line

Macros can be defined on the Make command line. For example:

make CFLAGS=–ms
would start up Make and define the macro CFLAGS with the value “–ms”. Macros defined on the command line take precedence over macros of the same name defined in the makefile.

If a command-line macro contains spaces, it must be enclosed in double quotes as in:

make “CFLAGS=-ms -z -p”

http://www.opussoftware.com/tutorial/TutMakefile.htm

April 16, 2012
Side by side comparison between ggplot2 and lattice…

Side by side comparison between ggplot2 and lattice
http://learnr.wordpress.com/tag/ggplot2/

Code examples and plot output
http://wiki.stdout.org/rcookbook/Graphs/

And of course,
http://had.co.nz/ggplot2/

April 5, 2012