--> missing value where TRUE/FALSE needed

Question

I have a problem with my code where it keep returning this error code repeatedly. Would definitely appreciate the help!

for (i in 1:length(X)) {
  if (Q[i] < 30) {
    Q2[i] = Q[i]
    for (i in i:length(X)) {
      if (Q[i + 1] < 30) {
        Q[i] = 0
        break
      }
    }
  }
  else {
    Q2[i] = Q[i]
  }
}

Error in if (Q[i + 1] < 30) { : missing value where TRUE/FALSE needed

Welcome to SO. Have a look at https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example . It will help you asking question in a better way. So that it will be easier to get help — MKR, Apr 01 '18 at 16:14
please provide some information on your data. What type of data is Q1 and Q2, are those dataframes, lists, vectors,....? Are there only num values or are there other values in it? are there NaN? — Michriko, Apr 01 '18 at 16:42
X is a vector of numerical values. Q and Q2 are just empty vectors that I have created to store the results of the loop. — Jj2000, Apr 01 '18 at 21:19

Elijah Moreau-Arnott · Answer 1 · 2018-04-16T15:38:16.697

You're looping i through 1 to the length of X.

At if (Q[i + 1] < 30) { you are attempting to access the element i+1. On the last iteration of the loop, i will be greater than the length of X.

To avoid this, you should only loop up to length(X) - 1

Furthermore, your inner-loop is using the same index variable as your outer loop:

for (i in i:length(X)) {

Other than just being bad practice, it's probably not doing what you intended. You should probably change the inner loop index to j:

for (j in i:length(X)) {

--> missing value where TRUE/FALSE needed

1 Answers1