**We will learn:**1. Vector Names

2. Plotting One Vectors

**Details:**This is part two of learning vectors in R programming language. If you haven't learned about the first part, you can

**start to learn vectors part one**.

###
**D. Vector Names**

For instance, I have three values (e.g. red, yellow and black) which is stored in

**wordlist**

__vector. That will be written as follows;__

**c**wordlist <- c("red","yellow","black") # wordlist stored "red", "yellow" and "black" value.

As explained in

*, when you need to pick one of the values, you can do like this:*

**Vector Access**rank[1:3]

Result: [1] "red","yellow","black"

Now, this time we will learn that "we can assign

*names*to a vector's elements by passing a second vector filled with names to the

**"names"****assignment function**".(

*taken from*. http://tryr.codeschool.com/levels/2/challenges/18) , as in:

names(wordlist) <- c("red","yellow","black")

**(Note**: to see more about names function in R, type:

help(names)

**)**

When we want to access or pick one of the values, we can type like this:

wordlist["yellow"]

Result: yellow

2

From the example above, that means, that we can access the value directly beside our common way, as in:

wordlist[2]

Result: yellow

2

From here, we also can change the position of "yellow" (that is: 2) to other position, for example, 7.

wordlist["yellow] <- 7

Now, see if it already changes:

wordlist["yellow"]

Result: "7"

or, with other way;

wordlist[7]

Result: "yellow"

###
**E. Plotting One Vector**

This section, we will learn about barplot. What is it?

**barplot**is

*R function*which is used to

*For further and details about that, just ask R to answer by typing: -*

**create vertical or horizontal bars (e.g. chart) with vector values.**help(barplot)

**Hint**: Talking about Vectors will force you to remember 2 things:

*and*

**Variables***.*

**Values**For example, we have ( again and again ... :p ) three values in c vector, they are: 3, 5 and 1, as follows:

1. Variable : stuDentS (

**warning**: case sensitive!)

2. Value: 3, 5, 1.

in R, as usual, you can type:

stuDentS<- c(3,5,1)

Then, let's start using barplot (hurrayyyy):

barplot(stuDentS)

Done! R will give us this amazing result!!!

Further, if you

*assign new names in the vector values*(... say,

*barney*,

*herman*and

*adhya*), R will take it as

*which will be placed below each bars based on the order you give.*

**Labels**For example:

names(stuDentS)<-c("Aminah","Herman","Adhya")

Then, R will give you this awesome chart!

Now, to show other types of chart, you can give range from 1 through 100, as in:

barplot(1:100)

Here's the result:

*See you on the next lesson :D*

*, my best regards.*