Remove the daily mean value from a multi-year time series. The time series t and y must be vectors of equal length and t must be daily values in datenum format.
y_deseasoned = deseason(t,y); returns the deseasoned y signal.
[y_ds,y_s] = deseason(t,y); returns the deseasoned y signal and the extracted seasonal signal such that y = y_s + y_ds.
[y_ds,y_s,annualsig] = deseason(t,y); also returns a vector of length 366 containing the annual signal where the index of annualsig corresponds to the day of the year.
This function requires Anthony Kendall's date2doy function available on the Mathworks FEX site: http://www.mathworks.com/matlabcentral/fileexchange/18316