R is a programming language and development environment for statistical computing and graphics. R is derived from S (a statistical programming language developed at Bell Labs). A friend of mine mentioned (*I am too lazy to check Wikipedia*) that R is named after the first names of the authors –* Oh the pomposity*. Joking aside, R is a very powerful programming language that greatly eases the development of statistical software for big data analysis.

#### Installing R

You can download R from here. Windows users - R comes in a 50 MB exe file that you download. R is available both for 32 bit and 64 bit OS versions. The installation is fairly straightforward.

#### R packages

R can be easily extended via user developed packages. At the time of writing this post R has around 5000 add on packages. *Translation: The R community is awesome*. To look at available packages select install packages from the package menu and pick a mirror from where to download.

#### Plotting a sine wave using R – Code with comments that are (hopefully) explanatory

The sine wave is the hello world of mathematics, physics, engineering…(I could go on). Let us begin our learning of R by plotting this venerable curve.

```
//the seq command generates sequences of numbers with the given step
t = seq(0, 10, by=0.001);
//set frequency to 1
freq = 1;
//the sine wave of frequency 1 hz
x = sin(2 * pi * freq * t);
//plot the sine wave
plot(t,x);
//turn on grid lines in a plot
grid();
```

**Voila - the sine wave**

#### Some helpful R functions

help(functionname) | Shows the help documentation for the function |

Ctrl + L | Clears the R console |

ls() | Lists the local variables |

search() | Shows a list of packages |

rm(objectname) | Removes an object from memory |

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