Lecture4_my-script-with-R_reshape
Jimmy(jmzeng1314@outlook.com)
Keywords: reshape2/melt/dcast
library(reshape2)
d=matrix(abs(rnorm(120)),ncol = 6)
rownames(d)=LETTERS[1:20]
colnames(d)=LETTERS[21:26]
dat=melt(d)
rownames(tmp)=tmp[,1]
tmp=tmp[,-1]
reshape是R base/stats的函数,主要用于数据框长格式和宽格式之间的转换。reshape函数的参数很多,不容易记,牛人Hadley Wickham搞出reshape和reshape2包以后这个函数几乎被人遗忘:
useful links : http://developer.51cto.com/art/201305/396615.htm