Hi Dennis, How about:
# define the two values to search for x<-2 y<-3 # create your search string and replacement string repstring<-paste(x,y,sep=",") newstring<-paste(x,y,sep=".") # this is the string that you want to change thetastring<-"SIGMA(2,3)" sub(repstring,newstring,thetastring) [1] "SIGMA(2.3)" Use gsub if you want to change multiple values Jim On Tue, Feb 13, 2018 at 1:22 PM, Dennis Fisher <fis...@plessthan.com> wrote: > R 3.4.2 > OS X > > Colleagues > > I would appreciate some help with regular expressions. > > I have string that looks like: > " ITERATION ,THETA1 ,THETA2 > ,THETA3 ,THETA4 ,THETA5 > ,THETA6 ,THETA7 ,SIGMA(1,1) > ,SIGMA(2,1) ,SIGMA(2,2)” > > In the entries that contain: > (X,Y) # for example, SIGMA(1,1) > I would like to replace the comma with a period, e.g., SIGMA(1.1) but NOT the > other commas > > The end-result would be: > " ITERATION ,THETA1 ,THETA2 > ,THETA3 ,THETA4 ,THETA5 > ,THETA6 ,THETA7 ,SIGMA(1.1) > ,SIGMA(2.1) ,SIGMA(2.2)” > > Can someone provide the regular expression code to accomplish this? > Thanks. > > Dennis > > Dennis Fisher MD > P < (The "P Less Than" Company) > Phone / Fax: 1-866-PLessThan (1-866-753-7784) > www.PLessThan.com > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.