Repeat printing bars in terminal when width is specified

[renkun-ken]

library(progress)

pb <- progress_bar$new(format = "processing [:bar] :percent :elapsed | :eta",
    total = 100, width = 80)

for (i in 1:100) {
  pb$tick()
  Sys.sleep(1 / 100)
}

If I run the code in RStudio, there's no problem at all. But if I run the code with rscript in terminal, then the progress bar is repeatedly printed out like

As long as I remove width argument, the problem is gone.

Here's my session info:

R version 3.2.0 (2015-04-16)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 8 x64 (build 9200)

locale:
[1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252 LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] progress_1.0.1

loaded via a namespace (and not attached):
 [1] magrittr_1.5      assertthat_0.1    R6_2.0.1          rversions_1.0.0   prettyunits_1.0.0
 [6] tools_3.2.0       rstudioapi_0.3.1  RCurl_1.95-4.6    memoise_0.2.1     git2r_0.10.1     
[11] digest_0.6.8      bitops_1.0-6      devtools_1.8.0    XML_3.98-1.2     

[gaborcsardi]

I guess this is because your screen is 80 characters wide. In this case you can only set width to 79 or less, otherwise the cursor moves to the next line, and a \r will not move it back to the previous line.

This is why width is set to getOption("width") - 2 by default. Technically minus one should be enough as well.

[gaborcsardi]

Please reopen if you still have problems.

[renkun-ken]

Your explanation perfectly solves my problem. Thanks!