04_tibble.Rmd

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title: "04_tibble"
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# 4.2 `tibble`:<br><br>Simple Data Frames

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## 4.2 `tibble`: Simple Data Frames

`tibble` provides an enhanced data frame object of class `tbl_df`, a so-called `tibble`. A `tibble` can be created in four different ways.

.panelset[
.panel[.panel-name[tibble()]
Create a `tibble` from column vectors with `tibble()`.
```{r}
tibble(
  x = c("a", "b"),
  y = c(1, 2),
  z = c(T, F)
)
```
]
.panel[.panel-name[tribble()]
Create a *transposed* `tibble` row by row with `tribble()`.
```{r}
tribble(
  ~x, ~y,  ~z,
  "a", 1,  T,
  "b", 2,  F
)
```
]
.panel[.panel-name[as_tibble()]
Create a `tibble` from an existing data frame with `as_tibble()`.
```{r}
data.frame(
  x = c("a", "b"),
  y = c(1, 2),
  z = c(T, F)
) %>% 
as_tibble
```
]
.panel[.panel-name[enframe()]
Create a `tibble` from named vectors with `enframe()`.
```{r}
c(x = "a", y = "b", z = 1) %>%
  enframe(name = "x", value = "y")
```
]
]

--

There are three important differences between a `tibble` and a `data.frame` object.

???
- named vector: i have key-value pairs

---

## 4.2 `tibble`: Simple Data Frames

**Printing:** By default, `tibble()` prints only the first ten rows and all the columns that fit on the screen as well as a description of the data type. This gives you a much more concise view of your data.
```{r}
penguins
```

???
- you will never again have the problem that `R` takes minutes to print a large data frame entirely to your console (`reached 'max' / getOption("max.print")`)

---

## 4.2 `tibble`: Simple Data Frames

**Printing:** By default, `tibble()` prints only the first ten rows and all the columns that fit on the screen as well as a description of the data type.

.panelset[
.panel[.panel-name[data.frame()]
```{r, echo=F}
options(max.print=40)
```

```{r}
data.frame(penguins)
```

```{r, echo=F}
options(max.print=1000)
```
]
.panel[.panel-name[tibble() (Option 1)]
```{r}
penguins
```
]
.panel[.panel-name[tibble() (Option 2)]
```{r}
penguins %>% glimpse
```
]
]

???
- in contrast to `data.frame()` which prints an extensive number of rows (wh)
`glimpse` transposed version of `print()`
 
---

## 4.2 `tibble`: Simple Data Frames

**Subsetting:** Subsetting a `tibble` (`[]`) always returns another `tibble` and never a vector (in contrast to standard `data.frame` objects).

.panelset[
.panel[.panel-name[data.frame()]
```{r}
data.frame(penguins) %>% .[,"species"] %>% class
```
]
.panel[.panel-name[tibble()]
```{r}
penguins[,"species"] %>% class
```
]
]

---

## 4.2 `tibble`: Simple Data Frames

**Partial Matching:** Subsetting a `tibble` does not allow for partial matching, i.e. you must always provide the whole column name.

.panelset[
.panel[.panel-name[data.frame()]
```{r, echo=F}
options(max.print=40)
```

```{r}
data.frame(penguins)$spec
```

```{r, echo=F}
options(max.print=1000)
```
]
.panel[.panel-name[tibble()]
```{r}
penguins$spec
```
]
]

???
- also an advantage of tibbles: Giving you better warning messages to confront you with problems early on.