The runlineDetrend GUI allows for the user to specify the runline detrending parameters. The detrending is done on a piecewise linear basis. The runlen parameter specifies the length of the window of the time series used to calculate the linear trend. Successive trends are calculated by running the window along the time series in steps of the size given by the parameter stepSize. When the RUN button is pressed, the detrending is invoked. Appropriate detrend parameters are very data dependent so the user can test the detrending by pressing display button to popup a detrend test window. The detrendTest shows an image that when clicked by the mouse plots the underlying time series in black with the calculated trend overlayed in red.