Question

在下面的代码中我遇到了错误：

运行时错误 while（x0tol）{：缺少值需要TRUE / FALSE时出错执行暂停

如果我注释掉循环，x0tol返回TRUE并且类逻辑。我错过了什么？提前谢谢。

a = c(1,2,2,3,3,4,5,6,6,6,8,10)
b = c(-890,1411,-1560,-2220,-2091,-2878,-3537,-3268,-3920,-4163,-5471,-5157)
data = data.frame(a,b)
tol = .0001
m = dim(data)[1]
x0 = 0
x1 = 0
x0temp = 1
x1temp = 1
alpha  = 1
x0tol = TRUE
while(x0tol){
    x0sum = 0
    x1sum = 0
    for (i in 1:m){ 
        x0sum = x0 + x1*data[m,1] - data[m,2]
        x1sum = (x0 + x1*data[m,1] - data[m,2])*data[m,1]
    }
    x0temp = x0 - alpha*1/m*x0sum
    x1temp = x1 - alpha*1/m*x1sum
    x0tol = (abs(x0 - x0temp) > tol) 
    x1tol = x1 - x1temp
    x0 = x0temp
    x1 = x1temp
    class(x0tol)
    x0tol
}

Answer 1

由于某种原因，它假设你的while循环条件中有一个NA值。只需更改语句并创建一个带有中断的If语句就应该允许循环起作用。干杯

while(TRUE){
  x0sum = 0
  x1sum = 0
  for (i in 1:m){ 
    x0sum = x0 + x1*data[m,1] - data[m,2]
    x1sum = (x0 + x1*data[m,1] - data[m,2])*data[m,1]
  }
  x0temp = x0 - alpha*1/m*x0sum
  x1temp = x1 - alpha*1/m*x1sum
  if (abs(x0 - x0temp) > tol){break}
  x1tol = x1 - x1temp
  x0 = x0temp
  x1 = x1temp
  class(x0tol)
  x0tol
}

逻辑变量和循环的问题

1 个答案: