How to control the limits of data values in R plots.
R has multiple graphics engines. Here we will talk about the base graphics and the ggplot2 package.
We’ll create a bit of data to use in the examples:
one2ten <- 1:10
ggplot2 demands that you have a data frame:
ggdat <- data.frame(first=one2ten, second=one2ten)
Seriously exciting data, yes?
The default is — not surprisingly — to create limits so that the data comfortably fit. Read more →
Several packages on CRAN provide (or relate to) interfaces between databases and R. Here is a summary, mostly in the words of the package descriptions. Remember that package names are case-sensitive.
The packages that talk about being DBI-compliant are referring to the DBI package (see below in “Other SQL”).
dbConnect: Provides a graphical user interface to connect with databases that use MySQL.
RMySQL: The current version complies with the database interface definition as implemented in the package DBI 0.2-2.
TSMySQL: TSMySQL provides a MySQL interface for TSdbi. Comprehensive examples of all the TS* packages are provided in the vignette Guide.pdf with the TSdata package. Read more →
Chapter 32 of Tao Te Programming advises you to make bricks instead of monoliths. Here is an example. The example is written with the syntax of R and is a data analysis, but the principle is valid no matter what language you use or what your task is.
Here is an outline of a function reminiscent of many novice attempts:
monolith <-
function (data, col="blue", pch=21)
{
# transform data
# fit model to data
# plot data, uses 'col' and 'pch'
# get desired model results
# return desired model results
}
Each of these comment lines may be many lines of code so that the whole function runs to pages. Read more →
