Question

由于大括号问题，我的代码无法正常工作

o1 = read.table('/Users/manshi/Desktop/PSYC57H3/PSYC57_Homework3/Object1.csv', header=TRUE, sep=",")
PredictedValue = vector(mode = 'numeric', length = 100)
PredictionError = vector(mode = 'numeric', length = 100)
PredictedValue[1] = 0
AlAccepts = vector(mode = 'logical', length = 100)
for (trial in 1:100){
  ifelse (AlAccepts[trial] == FALSE, 0, 1) {
    PredictionError[trial] = o1$Reward[trial] - PredictedValue[trial]
    PredictedValue[trial + 1] = PredictedValue[trial] + .3*PredictionError[trial]
  } ifelse (AlAccepts[trial] == TRUE, 0, 1) {
PredictedValue[trial + 1] = PredictedValue[trial]
  }
}

我收到的错误消息是：

> for (trial in 1:100){
+   ifelse (AlAccepts[trial] == FALSE, 0, 1) {
Error: unexpected '{' in:
"for (trial in 1:100){
  ifelse (AlAccepts[trial] == FALSE, 0, 1) {"
>     PredictionError[trial] = o1$Reward[trial] - PredictedValue[trial]
>     PredictedValue[trial + 1] = PredictedValue[trial] + .3*PredictionError[trial]
>   }   ifelse (AlAccepts[trial] == TRUE, 0, 1) {
Error: unexpected '}' in "  }"
>     PredictedValue[trial + 1] = PredictedValue[trial]
>   }
Error: unexpected '}' in "  }"
> }
Error: unexpected '}' in "}"
>

我做错了什么？

Answer 1

ifelse (AlAccepts[trial] == FALSE, 0, 1)是一个函数，并返回一个返回值，在这种情况下为0或1.未执行其他条件执行，因此以下括号显示语法错误。使用else if(){}应该按预期工作：

for (trial in 1:100){
  if (AlAccepts[trial] == FALSE) {
    PredictionError[trial] = o1$Reward[trial] - PredictedValue[trial]
    PredictedValue[trial + 1] = PredictedValue[trial] + .3*PredictionError[trial]
  } else if(AlAccepts[trial] == TRUE) {
PredictedValue[trial + 1] = PredictedValue[trial]
  }
}

卷曲括号问题 - for循环中的R - ifelse语句

1 个答案: