Re: [R] how to vectorize a for loop

hi: below almost gets you there except for the endpoints. see filter for more information. d=0.5 L=20 x=seq(20, by=1, length.out=20) temp <- as.numeric(filter(x,filter=c(d,(1-2*d),d),sides=2)) print(temp) On Sun, Nov 9, 2008 at 10:57 PM, stephen sefick wrote: #Is there a way to vectorize th

[R] how to vectorize a for loop

#Is there a way to vectorize the for loop #maybe a fancy indexing trick? #thanks d=0.5 L=20 x=seq(20, by=1, length.out=20) reflecting <- function(pre, d, L){ r=L-1 x=rep(0, L) for(j in 2:r){ x[j]=((1-(2*d))*pre[j])+(d*pre[(j+1)])+(d*pre[(j-1)]) } x[1