You're not using the correct Syntax for the selection method. I hope this will help.
// Selects row with key
table1.selectRow({ mode: 'key', key: 4 })
// Selects any visible row
table1.selectRow({mode: 'index', indexType: 'display', index: 4})
// Selects the row that represents table1.data[4]
table1.selectRow({mode: 'index', indexType: 'data', index: 4})