MARS模型的解决错误（“无法确定最终调整参数”）

我目前正在进行Max&Kjell的应用预测建模中的计算练习，在执行火星模型时遇到了上述标题中的错误

下面提供了所用软件包和代码的详细信息：

使用的软件包：AppliedPredictiveModeling和earth

marsFit <- earth(solTrainXtrans, solTrainY)

marsGrid <- expand.grid(degree = 1:2, nprune = 2:38)

set.seed(100)
marsTuned <- train(solTrainXtrans, solTrainY,
                   method = "earth",
                   # declaring the candidate models to test
                   tuneGrid = marsGrid,
                   trcontrol = trainControl(method = "cv")
                   )

有人能建议如何解决这个问题吗

Error in train.default(solTrainXtrans, solTrainY, method = "earth", tuneGrid = marsGrid,  : 
  final tuning parameters could not be determined
In addition: There were 50 or more warnings (use warnings() to see the first 50)