encounter error while reading files to summarizedExperiment

[baishengjun]

Hi,
I encountered error while reading files to summarizedExperiment using the test data.
Error in validObject(.Object) : invalid class "nmfExperiment" object: 1: invalid object for slot "FrobError" in class "nmfExperiment": got class "S4", should be or extend class "DataFrame" invalid class "nmfExperiment" object: 2: invalid object for slot "OptKStats" in class "nmfExperiment": got class "S4", should be or extend class "DataFrame" invalid class "nmfExperiment" object: 3: invalid object for slot "FeatureStats" in class "nmfExperiment": got class "S4", should be or extend class "DataFrame"
It seems the error from nmfExperiment when create object. I check the test data and processed step by step. How to solve it ?

Thanks a lot,
Bai