The FemPostObject class. writeVTK(filename) -> None Write data object to VTK file. filename: str File extension is automatically detected from data type. getDataset() -> vtkDataSet Returns the current output dataset. For normal filters this is equal to the objects Data property output. However, a pipelines Data property could store multiple frames, and hence Data can be of type vtkCompositeData, which is not a vtkDataset. To simplify implementations this function always returns a vtkDataSet, and for a pipeline it will be the dataset of the currently selected frame. Note that the returned value could be None, if no data is set at all.