Quantmod: buildmodel command with Error

When I use quantmod package there is a problem when I call buildModel command.

library(quantmod)
getSymbols("TSLA",from='2015-03-01')
q.model = specifyModel(Next(OpCl(TSLA)) ~ Lag(OpHi(TSLA),0:3),na.rm = T)
buildModel(q.model,method='lm',training.per=c('2015-09-01','2010-10-01'))

But there is is an error when I call buildModel

Error in eval(expr, envir, enclos) : object 'Next.OpCl.TSLA' not found

Does anyone know how to solve this problem?

Solution

As Pascal pointed out, there is a typo in your function : use 2015 instead of 2010 for your second date:

buildModel(q.model,method='lm',training.per=c('2015-09-01','2015-10-01'))
                                                               ^

If the dates are in chronological order I haven't got the problem any longer :

quantmod object:   lm1446193179.60143   Build date:  2015-10-30 09:17:52 

Model Specified: 
     Next(OpCl(TSLA)) ~ Lag(OpHi(TSLA), 0:3) 

Model Target:  Next.OpCl.TSLA        Product:  TSLA 
Model Inputs:  Lag.OpHi.TSLA.0.3.Lag.0, Lag.OpHi.TSLA.0.3.Lag.1, Lag.OpHi.TSLA.0.3.Lag.2, Lag.OpHi.TSLA.0.3.Lag.3 

Fitted Model: 

    Modelling procedure:  lm 
    Training window:  22  observations from  2015-09-01 to 2015-10-01

Call:
lm(formula = [email protected], data = training.data)

Coefficients:
            (Intercept)  Lag.OpHi.TSLA.0.3.Lag.0  Lag.OpHi.TSLA.0.3.Lag.1  
              -0.001594                -0.147112                -0.041063  
Lag.OpHi.TSLA.0.3.Lag.2  Lag.OpHi.TSLA.0.3.Lag.3  
               0.261051                -0.023408