An Annotated R History Log - Part 2

quit() - end the current R session. q() works too.

x<-c(1,2,4,5) - Create a vector containing the numbers given.

mean(x) - calculate the mean of those numbers

barplot(x) - chart the values of x. Starting to get interesting.

abline(h=mean(x)) - add an a-b line to the previous plot. The line is horizontal with a height of mean(x). Useful for adding 'targets' to a chart.

help(package=ggplot2) - an extended use of the help function. Profice a value to the package parameter.

data() - list the data sources available in the current session.

AirPassengers - One of the included datasets. Entering it like this just prints it.

plot(AirPassengers) - produce a plot of the number of air passengers over time. This is what it looks like. I am a long way from being able to quantify that seasonal variation, but it is an interesting thing to look at when I know how.

AirPassengers plot

women - dataset of womens height vs weight.

plot(women$height, women$weight) - plots a scatter of womens weight vs weight, but unnecessary as the data is in columns. plot(women) would do the same job.

mdeaths - this one is the monthly deaths from lung disease in the UK.

Note that you can use tab to autocomplete a lot of stuff in R. For example datasets. There are a large number of them and tab allows you to pick out the ones you need nice and quick.

Note: Typing help(dataset) gives you information on the dataset, including sources.

uspop - population of the United States.

There are a lot of datasets that some with R. They are in nice formats unlike most of the stuff I have tried to play with so far. Hopefully with increased skill I will be able to press the data into the format I need to plot and manipulate it.