# fill_gap: Add rows corresponding to gaps in some variable In statar: Tools Inspired by 'Stata' to Manipulate Tabular Data

## Description

Add rows corresponding to gaps in some variable

## Usage

 ```1 2 3``` ```fill_gap(x, ..., full = FALSE, roll = FALSE, rollends = if (roll == "nearest") c(TRUE, TRUE) else if (roll >= 0) c(FALSE, TRUE) else c(TRUE, FALSE)) ```

## Arguments

 `x` A data frame `...` a time variable `full` A boolean. When full = FALSE (default) rows are filled with respect to min and max of `...` within each group. When full = TRUE, rows are filled with respect to min and max of `...` in the whole datasets. `roll` When roll is a positive number, this limits how far values are carried forward. roll=TRUE is equivalent to roll=+Inf. When roll is a negative number, values are rolled backwards; i.e., next observation carried backwards (NOCB). Use -Inf for unlimited roll back. When roll is "nearest", the nearest value is used. `rollends` A logical vector length 2 (a single logical is recycled). When rolling forward (e.g. roll=TRUE) if a value is past the last observation within each group defined by the join columns, rollends[2]=TRUE will roll the last value forwards. rollends[1]=TRUE will roll the first value backwards if the value is before it. If rollends=FALSE the value of i must fall in a gap in x but not after the end or before the beginning of the data, for that group defined by all but the last join column. When roll is a finite number, that limit is also applied when rolling the end

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11``` ```library(dplyr) library(lubridate) df <- data_frame( id = c(1, 1, 1, 2), datem = as.monthly(mdy(c("04/03/1992", "01/04/1992", "03/15/1992", "05/11/1992"))), value = c(4.1, 4.5, 3.3, 3.2) ) df %>% group_by(id) %>% fill_gap(datem) df %>% group_by(id) %>% fill_gap(datem, full = TRUE) df %>% group_by(id) %>% fill_gap(datem, roll = "nearest") df %>% group_by(id) %>% fill_gap(datem, roll = "nearest", full = TRUE) ```

statar documentation built on July 6, 2017, 5:03 p.m.