Y = windex(X,W,Range)
X [ tseries ] - Input times series.
W [ tseries | numeric ] - Fixed or time-varying weights on the input time series.
Range [ numeric ] - Range on which the Divisia index is computed.
Y [ tseries ] - Weighted index based on X.'method=' [ 'divisia' | 'simple' ] - Weighting method.
'log=' [ true | false ] - Logarithmise the input data before computing the index, delogarithmise the output data.