This function plots a heat map to visualize the coverage of the time-scope-units of the data. Options include total number of cases per time-scope-unit or relative number in percentage.

## Usage

```
overview_heat(
dat,
id,
time,
perc = FALSE,
exp_total = NULL,
xaxis = "Time frame",
yaxis = "Sample",
col_low = "#dceaf2",
col_high = "#2A5773",
label = TRUE
)
```

## Arguments

- dat
The data set

- id
The scope (e.g., country codes or individual IDs). The axis is ordered in ascending order by default.

- time
The time (e.g., time periods given by years, months, ...)

- perc
If FALSE (default) plot returns the total number of observations per time-scope-unit. If TRUE, it returns the number of observations per time-scope-unit in percentage

- exp_total
Expected total number of observations (i.e. maximum) for time unit.

- xaxis
Label of your x axis ("Time frame" is default)

- yaxis
Label of your y axis ("Sample" is default)

- col_low
Hex color code for the lowest value (default is "#dceaf2")

- col_high
Hex color code for the lowest value (default is "#2A5773")

- label
If TRUE (default), the total number of observations/percentages of observations are displayed. If FALSE, it returns no labels.

## Examples

```
data(toydata)
overview_heat(toydata, ccode, year, perc = TRUE, exp_total = 12)
```