looping between two vectors for meeting three conditions - r

Question

I have a csv file containing 4 columns of data. I need to select the first column from the csv file which I do like this:
file1<-read.csv("file1.csv",header=TRUE)
x<-file[,1]
The first column contains (x, here) contains row numbers.
x
5
10
54
177
178
182
183
184
185
203
204
205
206
207
208
Now there is another csv file which contains a single column of 365 rows of data
y<-read.csv("data.csv",header=TRUE)
y
0
2.3
0.5
21
0
.
.
.
9.5 #total 365 numbers
This is what I intend to do:
1) From x, chose the first number (which is 5)
2) In y, select the corresponding 5th data point (which is 0) and 4 data point prior to it (which are 21,0.5,2.3,0), then test the following condition respectively
Condition 1: From the 5 data points, if the three out of five are > 0, then print 5 (result of step 1)
Condition 2: If all four of five are >0, then print 5 again
Condition 3: If all of five are >0, then print 5 again
However, if out of three conditions, only the first two are met and third one is not met, then select the second number from x (10 in this case) and again choose the corresponding 10th data point in y and four data points prior to it (6th,7th,8th and 9th) and evaluate them for the third condition (i.e. if all the five numbers - 6th, 7th, 8th,9th and 10th are > 0, I do not need to evaluate the first and second condition which are already met by the previous number from x),then save 10 and stop.
This sounds quite complicated for a feeble mind of mine (as seen by my reputation) and was hoping someone can tell me how to do this in R.
Thanks a lot

Answer 1

Sounds like you need a while loop.
file1 <- data.frame(x=seq(5, 205, by=5))
file1
x <- file1[, 1]
set.seed(123)
file2 <- data.frame(y=rnorm(365))
y <- file2[, 1]
# flags for each condition
cond1 <- FALSE
cond2 <- FALSE
cond3 <- FALSE
k <- 0
while(!cond3) {
k <- k + 1
# select first number
num <- x[k]
# select all y's up to data point
all.y <- y[(num-4):num]
# number of positive values
chk.pos <- length(which(all.y > 0))
# condition 1: check if 3 of 5 are positive
cnt <- 0
if (!cond1 & chk.pos >= 3) {
cnt <- cnt + 1
cond1 <- TRUE
print(num)
}
# condition 2: check if 4 of 5 are positive
if (!cond2 & chk.pos >= 4) {
cnt <- cnt + 1
cond2 <- TRUE
print(num)
}
# condition 3: check if 5 of 5 are positive
if (!cond3 & chk.pos == 5) {
cnt <- cnt + 1
cond3 <- TRUE
print(num)
}
}
for me returns
[1] 5
[1] 15
[1] 70