Calculates the number of incomplete cases.

## Examples

```
nic(nhanes) # the remaining 12 rows
#> [1] 12
nic(nhanes[, c("bmi", "hyp")]) # number of cases with incomplete bmi and hyp
#> [1] 9
```

Calculates the number of incomplete cases.

```
nic(nhanes) # the remaining 12 rows
#> [1] 12
nic(nhanes[, c("bmi", "hyp")]) # number of cases with incomplete bmi and hyp
#> [1] 9
```