# Subsets in R

As you might imagine, selecting a specific column from a data frame is a common manipulation. So common, in fact, that it was given its own shortcut, the `$`

. The following return the same answer:

```
cash$cash_flow
[1] 1000 4000 550 1500 1100 750 6000
cash[,"cash_flow"]
[1] 1000 4000 550 1500 1100 750 6000
```

Useful right? Try it out!

Often, just simply selecting a column from a data frame is not all you want to do. What if you are only interested in the cash flows from company A? For more flexibility, try subset()!

```
subset(cash, company == "A")
company cash_flow year
1 A 1000 1
2 A 4000 3
3 A 550 4
```

There are a few important things happening here:

- The first argument you pass to
`subset()`

is the name of your data frame,`cash`

. - Notice that you shouldn't put
`company`

in quotes! - The
`==`

is the equality operator. It tests to find where two things are equal, and returns a logical vector.

## Exercise

TRY IT YOURSELF: Access the exercise in our Introduction to R for Finance course here.

- Use
`subset()`

to select only the rows of`cash`

corresponding to company B. - Now
`subset()`

rows that have cash flows due in 1 year.

```
# Rows about company B
# Rows with cash flows due in 1 year
```

## Video

To learn more about accessing and subsetting dataframes in R, please see this video from our course Introduction to R for Finance.

This content is taken from DataCamp’s Introduction to R for Finance course by Lore Dirick.