lasso periodically fails

[tobigithub]

Method "lasso" in caret fails from time to time with

Error in { : 
  task 1 failed - "arguments imply differing number of rows: 3, 2"

example code

# load caret and DT the cars data set
require(caret); require(DT);  

# define x and y for regression of a synthetic dataset
# defined in lasso 
set.seed(123); training_data <- SLC14_1(10)
set.seed(123); testing_data  <- SLC14_1(100)

# all the training data (just named x and y)
y <- training_data$y
x <- training_data[, -ncol(training_data)]

train(x,y,"lasso")
train(x,y,"lasso")
train(x,y,"lasso")

results in

> train(x,y,"lasso")
The lasso 

10 samples
20 predictors

No pre-processing
Resampling: Bootstrapped (25 reps) 
Summary of sample sizes: 10, 10, 10, 10, 10, 10, ... 
Resampling results across tuning parameters:

  fraction  RMSE      Rsquared   RMSE SD    Rsquared SD
  0.1       11.37634  0.3940539   3.556101  0.2981656  
  0.5       17.29988  0.4252108  13.101637  0.3506784  
  0.9       24.54744  0.4397249  26.254093  0.3695557  

RMSE was used to select the optimal model using  the smallest value.
The final value used for the model was fraction = 0.1. 
> train(x,y,"lasso")
Error in { : 
  task 1 failed - "arguments imply differing number of rows: 3, 2"