inputFolder = '/Input'
inputTimeseries1 = 'Input1'
inputTimeseries2 = 'Input2'
outputFolder = '/Output'
outputName = 'OutputTimeseries'
formula = '[Input1]-[Input2]'
    
tsMgr = app.Modules.Get('Time series Manager')
ts1 = tsMgr.TimeSeriesList.Fetch(inputFolder + '/' + inputTimeseries1)
ts2 = tsMgr.TimeSeriesList.Fetch(inputFolder + '/' + inputTimeseries2)
mapping = {inputTimeseries1 : ts1, inputTimeseries2: ts2}
    
tool = app.Tools.CreateNew('Timeseries Calculator')
tool.InputItems.Add(ts1)
tool.InputItems.Add(ts2)
tool.Formula = formula
tool.NameMapping = mapping
tool.Execute()
output = tool.OutputItems[0]

outputGroup = tsMgr.TimeSeriesGroupList.Fetch(outputFolder)
if(outputGroup != None):
    output.GroupId = outputGroup.Id
    
outputTS = tsMgr.TimeSeriesList.Fetch(outputFolder + '/' + outputName)
if(outputTS == None):
    output.Name = outputName
    tsMgr.TimeSeriesList.Add(output)
else:
    print 'timeseries already exists'