Set Scatter Chart Type In Phpexcel

I need to remove the lines in my Scatter Chart. I tried modifying files in the PHPExcel’s Chart folder but none of my workarounds solved my problem. I think you’re supposed to set STYLE_MARKER in the array below but it doesn’t seem to work.

$series = new PHPExcel_Chart_DataSeries(

PHPExcel_Chart_DataSeries::TYPE_SCATTERCHART,   // plotType

NULL,                                           // plotGrouping (Scatter charts don't have any grouping)

range(0, count($dataSeriesValues)-1),           // plotOrder

$dataseriesLabels,                              // plotLabel

$xAxisTickValues,                               // plotCategory

$dataSeriesValues,                              // plotValues

NULL,                                           // smooth line

PHPExcel_Chart_DataSeries::STYLE_MARKER     // plotStyle);

Any ideas?