search for: subtractin

...ect is clever enough to object. So I guess I need to write a function for subtraction of the time series objects which will need to interpolate the samples to the same sampling time (this linear interpolation should be ok here) I would like to make this function the default one to be used when a ts subtractin is attempted. Unfortunatly I dont really have much idea where to start with this. If someone could point me in the direction of some good reading I'll be grateful. Many thanks (again) Tom