| loop.tracker {NCmisc} | R Documentation |
Creates a progess bar within a loop
Description
Only requires a single line within a loop to run, in contrast with the built-in tracker which requires a line to initialise, and a line to close. Also has option to backup objects during long loops. Ideal for a loop with a counter such as a for loop. Tracks progress as either percentage of time remaining or by intermittently displaying the estimated number of minutes to go
Usage
loop.tracker(
cc,
max,
st.time = NULL,
sav.obj = NULL,
sav.fn = NA,
sav.freq = 10,
unit = c("m", "s", "h")[1]
)
Arguments
cc |
integer, current value of the loop counter |
max |
integer, final value of the loop counter |
st.time |
'start time' when using 'time to go' mode, taken from a call to proc.time() |
sav.obj |
optionally an object to backup during the course of a very long loop, to restore in the event of a crash. |
sav.fn |
the file name to save 'save.obj' |
sav.freq |
how often to update 'sav.obj' to file, in terms of percentage of run-time |
unit |
time units h/m/s if using 'time to go' mode |
Value
returns nothing, simply prints progress to the console
Author(s)
Nicholas Cooper njcooper@gmx.co.uk
Examples
# simple example with a for-loop
max <- 100; for (cc in 1:max) { loop.tracker(cc,max); wait(0.004,"s") }
#example using the 'time to go' with a while loop
cc <- 0; max <- 10; start <- proc.time()
while(cc < max) { cc <- cc + 1; wait(0.05,"s"); loop.tracker(cc,max,start,unit="s") }
# example with saving an object, and restoring after a crash
X <- matrix(rnorm(5000),nrow=50); max <- nrow(X); sums <- numeric(max)
for (cc in 1:max) {
sums[cc] <- sum(X[cc,])
wait(.05) # just so this trivial loop doesn't finish so quickly
loop.tracker(cc,max, sav.obj=sums, sav.fn="temp.rda", sav.freq=5);
if(cc==29) { warning("faked a crash at iteration 29!"); rm(sums); break }
}
cat("\nloaded latest backup from iteration 28:",paste(load("temp.rda")),"\n")
print(sav.obj); unlink("temp.rda")