stat405

Homework 5

Due in class, Wednesday 7 Oct.

Choose one group of functions from the following list:

cummax, cummin, cumprod, cumsum, diff
max, min, prod, sum

&, |, !, xor, all, any
intersect, union, setdiff

help, ?, example
help.search, RSiteSearch
citation

```
rep, rep.int, seq, seq_along, seq_len
```
```
cut, findInterval, tabulate
```

acos, acosh, asin, asinh, atan, atan2, atanh
sin, sinh, cos, cosh, tan, tanh
ceiling, floor, round, trunc, signif
exp, log, log10, log1p, log2, logb, sqrt

(Hint: the fewer the functions, the more complicated each individual one will be)

You job is to make a quick reference sheet for the group of functions you have chosen. The first thing you'll need to do is figure out why they are a group (i.e. what do they have in common and how do they differ?) and come up with a good name for the reference sheet. Do that by looking at the help for each function (?acos or help("|")).

The sheet should:

Give a brief summary of each function, with closely related functions grouped together. You can assume the reader has a decent mathematical background.
Provide some examples of function use. You should try and exercise a wide range of the functionality, and compare and contrast the different functions.
Be prepared in latex. If you want to make a table (a good idea!), see this tutorial for the basics, and the booktabs package to make prettier tables.

Here is a very quick example I made up about matrix algebra. Be sure to read my comments in the tex source. If you get stuck, or can't see how the functions are related, please see me!

Some great answers from this year

On logical and set operations: a, b.
On intervals

Two great answers from last year

If you choose to work on the same group of functions I'll expect something even better!