require 'win32ole'
ChartTypeVal = 4100;
excel = WIN32OLE.new("excel.application")
excel['Visible'] = TRUE
excel.Workbooks.Add()
excel.Range("a1")['Value'] = 3
excel.Range("a2")['Value'] = 2
excel.Range("a3")['Value'] = 1
excel.Range("a1:a3").Select()
excelchart = excel.Charts.Add()
excelchart['Type'] = ChartTypeVal
30.step(180, 5) do |rot|
excelchart.rotation = rot
sleep(0.1)
end
excel.ActiveWorkbook.Close(0)
excel.Quit()