thanks for your help, it is great. In addition, In the beginning, the format of x is dataframe, and i run my code, it is so slow, after your help, I change x for matirx, it is so quick. I am very grateful your kind help, and your code is so good!
kevin -- View this message in context: http://r.789695.n4.nabble.com/how-to-replace-my-double-for-loop-which-is-little-efficient-tp3164222p3164732.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
