[R] How to get rid of loop?

[Ken-JP]

The code below shows what I'm trying to get rid of.

If there is no way to get rid of the loop, I will try to use package( inline
).
I'm just curious as to whether there is a "vector way" of doing this
algorithm.

#
-----------------------------------------------------------------------------------------

set.seed(1)
x <- runif(100)
n <- length( x )
y <- rep(NA, n)
yprev <- 0;
for ( i in (1:n)) {
	if ( x[i]>0.75 ) {
		y[i] <- 1;
	} else if ( x[i]<0.25 ) {
		y[i] <- -1;
	} else if ( yprev==1 & x[i]<0.5) {
		y[i] <- 0;
	} else if ( yprev==-1 & x[i]>0.5) {
		y[i] <- 0;
	} else {
		y[i] <- yprev
	}
	yprev <- y[i];
}

> y
  [1]  0  0  0  1 -1  1  1  1  1 -1 -1 -1  0  0  1  0  0  1  0  1  1 -1  0
-1 -1
 [26] -1 -1 -1  1  0  0  0  0 -1  1  1  1 -1  0  0  1  1  1  1  1  1 -1 -1 
0  0
 [51]  0  1  0 -1 -1 -1 -1  0  0  0  1  0  0  0  0  0  0  1 -1  1  0  1  0 
0  0
 [76]  1  1  0  1  1  0  0  0  0  1 -1  0 -1 -1 -1 -1 -1  0  1  1  1  0  0 
1  1


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