<!--
%\VignetteIndexEntry{Progress updates for 'lme4' functions}
%\VignetteAuthor{Henrik Bengtsson}
%\VignetteKeyword{R}
%\VignetteKeyword{package}
%\VignetteKeyword{lme4}
%\VignetteKeyword{vignette}
%\VignetteKeyword{progressify}
%\VignetteEngine{progressify::selfonly}
-->

The **progressify** package allows you to easily add progress
reporting to sequential and parallel map-reduce code by piping to the
`progressify()` function. Easy!


# TL;DR

```r
library(progressify)
handlers(global = TRUE)
library(lme4)

# Fit random-slope model
fm1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy)
my_stat <- function(fit) {
  fixef(fit)
}

# Run bootstrap with progress signaling
res <- bootMer(fm1, my_stat, nsim = 1000) |> progressify()
```


# Introduction

This vignette demonstrates how to use this approach to add progress
reporting to **[lme4]** functions such as `bootMer()`. The **lme4**
package provides functions for fitting linear, generalized linear, and
nonlinear mixed-effects models. For example, `bootMer()` runs a
statistic function `nsim` times:

```r
library(lme4)

# Fit random-slope model
fm1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy)
my_stat <- function(fit) {
  fixef(fit)
}

res <- bootMer(fm1, my_stat, nsim = 1000)
```

By default, `bootMer()` provides no progress feedback. However, we can
easily add progress reporting using the `progressify()` function:

```r
library(lme4)
library(progressify)
handlers(global = TRUE)

# Fit random-slope model
fm1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy)
my_stat <- function(fit) {
  fixef(fit)
}

res <- bootMer(fm1, my_stat, nsim = 1000) |> progressify()
```


# Supported Functions

The `progressify()` function supports the following **lme4**
functions:

 * `bootMer()`


[lme4]: https://cran.r-project.org/package=lme4