Hello dear R users! I did not find a function which gives information about the number of digits of a value shown by R. Do you know one?
I need it to solve the problem (see RFAQ 7.31)that 0.2==0.2+0.1-0.1 FALSE The solution suggested in RFAQ is to use isTRUE(all.equal(0.2,0.2+0.1-0.1)) But if I want to compare inequality: 0.2<=0.2 +0.1-0.1 TRUE but 0.2<=0.2 +0.1-0.1 FALSE bad! but in this case all.equal does not work I think... Unless to write a double condition like 0.2>0.2 +0.1-0.1 | isTRUE(all.equal(0.2,0.2 +0.1-0.1)) The solution I found is to round the values, because 0.2==round(0.2+0.1-0.1,2) TRUE However, one has to know the number of digits of the target value. How can you do when it is unknown? What I mean is if R shows 2.3456 I want to obtain the info that digits=4 even if in facts the value has more (internal) digits. I did not find a way to represent the number of digits but I found that as.numeric(as.character(x)) rounds the values to the number of digits shown. But is there a better way to make it? Thanks! ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
