将Rdata和图形保存在循环中

Question

I need to save some graphs and Rdata in a loop-like behaviour. I have made a short example of what I need done. My problem is in my code the graph just overwrites each other, so I guess I am having trouble with dynamically naming them.

for (i in seq(from = 100, to = 2000, by = 100)){
  x <- rnorm(1:3000)
  x <- x[seq(from=1, to=length(x),i)]

  e=0
  d <- matrix(ncol = 1, nrow = 91)
  for (f in seq(from=1, to=10,by=0.1)) { 
    e=e+1
    d[e] <- sum(abs(x)^f)
  }

  x = data.frame(d);
  names(x)='V1';
  x$V2 = seq(from = 1, to = 10, by = 0.1);


pdf("C:/Users/x.pdf", height=6, width=6)

ggplot(x, aes(x=x$V2, y = x$V1)) + 
  geom_line(alpha=1)

dev.off()

save.image(file = "output.Rdata")

}

Thanks!

Answer 1

I think the problem is that you are writing to the same file name "x" every time, without incrementing the file name on subsequent iterations of the loop. For example:

for (i in 1:10) { pdf(file=paste(i, "x.pdf", sep="")) plot(rnorm(1:10)) dev.off() }

The above would name the files x1.pdf, x2.pdf, x3.pdf... x10.pdf. Without the "i", each iteration would write to x.pdf.

Alternatively, you could make a call to pdf at the start of the loop before the curly braces. Then dev.off() after the final curly brace.