R 使用带有多个变量的 For 循环时出现意外括号错误

Question

I am new to R and writing a stock trading model. The initial working code is below.

Initiate Signal
rsi <- RSI(price, day)  #rsi is the lag of RSI
for (i in (day+1): length(price)){
  if (rsi[i] < 30){  #buy one more unit if rsi < 30
    signal[i] <- 1
  } else if (rsi[i] < 50){ #no change if rsi < 50
    signal[i] <- 0
  } else {         #sell  if rsi > 50
    signal[i] <- -1
  }
}

The problem with above is that it keeps generating trading signal everytime RSI is less than 30. Hence i created a dummy_var which is updated during the loop. A sell is triggered when there is an existing buy signal ieif the value of dummy_var= 2 and buy when dummy_var=1. But i keep getting this error message - Error: unexpected '}' in " }" . Kindly help.

for (i in (day+1): length(price)){
  if (dummy_var=2){
    (rsi[i] < 50)  #no change if rsi < 50
    signal[i] <- 0
    dummy_var <- 2
  } else if (dummy_var = 2){
    (rsi[i] > 50) # sell if great than 50
    signal[i] <- -1
    dummy_var <- 2
  } else (rsi[i] < 30){
    signal[i] <- 1
    (dummy_var <- 2)
  }
}

Answer 1

There is an error in your condition:

if (dummy_var=2)

The = is used to assign a value. In your case you want to check if dummy_var equals 2 , therefore you have to use

if (dummy_var == 2)