[R] Rprintf not updating

Erik Wright eswright at wisc.edu
Mon Apr 5 16:58:37 CEST 2010

Hello all,

I am using Rprintf in a C for loop (from .Call) to print a progress indicator showing the current percent complete. The loop I am doing is an time intensive call to another function.  I have noticed that Rprintf does not print to the R-window until the entire loop has been completed.  When it reaches the end of the loop it suddenly prints 0 percent to 100 percent in a split second.  For less intensive function calls it prints properly while looping.  My question is this:  is there any way to force Rprintf to print to the screen during a loop?

On a related note, how can I show a percent sign in the output?  For example, Rprintf("0%"); only prints a zero.


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