Creating Progress Bar and Setting Options

Creating progress bar and setting options.

Usage

pboptions(...)
startpb(min = 0, max = 1)
setpb(pb, value)
getpb(pb)
closepb(pb)
dopb()
doshiny()
pbtypes()

Arguments

...: Arguments in tag = value form, or a list of tagged values. The tags must come from the parameters described below.
pb: A progress bar object created by startpb.
min, max: Finite numeric values for the extremes of the progress bar. Must have min < max.
value: New value for the progress bar.

Details

pboptions is a convenient way of handling options related to progress bar.

Other functions can be used for conveniently adding progress bar to for-like loops (see Examples).

Value

When parameters are set by pboptions, their former values are returned in an invisible named list. Such a list can be passed as an argument to pboptions to restore the parameter values. Tags are the following:

type: Type of the progress bar: timer ("timer"), text ("txt"), Windows ("win"), TclTk ("tk"), none ("none"), or Shiny ("shiny"). Default value is "timer" progress bar with estimated remaining time when in interactive mode, and "none" otherwise. See pbtypes() for available progress bar types depending on operating system.
char: The character (or character string) to form the progress bar. Default value is "+".
txt.width: The width of the text based progress bar, as a multiple of the width of char. If NA, the number of characters is that which fits into getOption("width"). Default value is 50.
gui.width: The width of the GUI based progress bar in pixels: the dialogue box will be 40 pixels wider (plus frame). Default value is 300.
style: The style of the bar, see txtProgressBar and timerProgressBar. Default value is 3.
initial: Initial value for the progress bar. Default value is 0.
title: Character string giving the window title on the GUI dialogue box. Default value is "R progress bar".
label: Character string giving the window label on the GUI dialogue box. Default value is "".
nout: Integer, the maximum number of times the progress bar is updated. The default value is 100. Smaller value minimizes the running time overhead related to updating the progress bar. This can be especially important for forking type parallel runs.
min_time: Minimum time in seconds. timerProgressBar output is printed only if estimated completion time is higher than this value. The default value is 0.
use_lb: Switch for using load balancing when running in parallel clusters. The default value is FALSE.

For startpb a progress bar object.

For getpb and setpb, a length-one numeric vector giving the previous value (invisibly for setpb). The return value is NULL if the progress bar is turned off by getOption("pboptions")$type ("none" or NULL value).

dopb returns a logical value if progress bar is to be shown based on the option getOption("pboptions")$type. It is FALSE if the type of progress bar is "none" or NULL.

doshiny returns a logical value, TRUE when the shiny package namespace is available (i.e. the suggested package is installed), the type option is set to "shiny", and a shiny application is running.

For closepb closes the connection for the progress bar.

pbtypes prints the available progress bar types depending on the operating system (i.e. "win" available on Windows only).

Author

Peter Solymos <solymos@ualberta.ca>

Examples

## increase sluggishness to admire the progress bar longer
sluggishness <- 0.01

## for loop
fun1 <- function() {
    pb <- startpb(0, 10)
    on.exit(closepb(pb))
    for (i in 1:10) {
        Sys.sleep(sluggishness)
        setpb(pb, i)
    }
    invisible(NULL)
}
## while loop
fun2 <- function() {
    pb <- startpb(0, 10-1)
    on.exit(closepb(pb))
    i <- 1
    while (i < 10) {
        Sys.sleep(sluggishness)
        setpb(pb, i)
        i <- i + 1
    }
    invisible(NULL)
}
## using original settings
fun1()
## resetting pboptions
opb <- pboptions(style = 1, char = ">")
## check new settings
getOption("pboptions")
#> $type
#> [1] "none"
#> 
#> $char
#> [1] ">"
#> 
#> $txt.width
#> [1] 50
#> 
#> $gui.width
#> [1] 300
#> 
#> $style
#> [1] 1
#> 
#> $initial
#> [1] 0
#> 
#> $title
#> [1] "R progress bar"
#> 
#> $label
#> [1] ""
#> 
#> $nout
#> [1] 100
#> 
#> $min_time
#> [1] 0
#> 
#> $use_lb
#> [1] FALSE
#> 
## running again with new settings
fun2()
## resetting original
pboptions(opb)
## check reset
getOption("pboptions")
#> $type
#> [1] "none"
#> 
#> $char
#> [1] "+"
#> 
#> $txt.width
#> [1] 50
#> 
#> $gui.width
#> [1] 300
#> 
#> $style
#> [1] 3
#> 
#> $initial
#> [1] 0
#> 
#> $title
#> [1] "R progress bar"
#> 
#> $label
#> [1] ""
#> 
#> $nout
#> [1] 100
#> 
#> $min_time
#> [1] 0
#> 
#> $use_lb
#> [1] FALSE
#> 
fun1()

## dealing with nested progress bars
## when only one the 1st one is needed
f <- function(x) Sys.sleep(sluggishness)
g <- function(x) pblapply(1:10, f)
tmp <- lapply(1:10, g) # undesirable
## here is the desirable solution
h <- function(x) {
    opb <- pboptions(type="none")
    on.exit(pboptions(opb))
    pblapply(1:10, f)
}
tmp <- pblapply(1:10, h)

## list available pb types
pbtypes()
#> [1] "timer" "txt"   "tk"    "none"  "shiny"