Insert a row to a data table

from Spotfire.Dxp.Data import AddRowsSettings
import System
from System import DateTime
from System.IO import StringReader, StreamReader, StreamWriter, MemoryStream, SeekOrigin
from Spotfire.Dxp.Data import DataType, DataTableSaveSettings
from Spotfire.Dxp.Data.Import import TextFileDataSource, TextDataReaderSettings

#First we need to create your data with some columns. 
#Here I have a comma separated miniature table built up with 
#a commented option for your variable itself. \r\n used for newline
data_for_new_row= "val1,val2,val3"
textData = "col1,col2,col3\r\n" + data_for_new_row + "\r\n"

#Memory Stream stuff. Simply just writing our variable 
#into a place we can access to make a data source
stream = MemoryStream()
writer = StreamWriter(stream)
writer.Write(textData)
writer.Flush()
stream.Seek(0, SeekOrigin.Begin)

#you need settings to tell the system what stuff you're importing.
#here we define it is comma separated and what data types our columns are.
readerSettings = TextDataReaderSettings()
readerSettings.Separator = ","
readerSettings.AddColumnNameRow(0)
readerSettings.SetDataType(0, DataType.String)
readerSettings.SetDataType(1, DataType.Integer)
readerSettings.SetDataType(2, DataType.String)
textDataSource = TextFileDataSource(stream,readerSettings)

#We create some settings here automatically having the system match
#column names for us between the data table and our data source.
settings = AddRowsSettings(dataTable,textDataSource)

#And finally we add the rows from our datasource with our settings.
dataTable.AddRows(textDataSource,settings)

Reference here