LST_SQU_HARMONICS - Removes harmonics (typically tides) from HFRC objects. This functions uses a least squares method to remove tidal (or any other frequency component) from current data. It is suitable for removal of tides and comparison of amplitudes and phases between different objects, but is not suitable for full tidal analysis and prediction. Use the t_tide method for that. It fits the given data to: U(t) = sum_i=1_to_n ( AU_i * cos( 2*pi*f_i*t - theta_U_i ) ) V(t) = sum_i=1_to_n ( AV_i * cos( 2*pi*f_i*t - theta_V_i ) ) Usage: hfrc_notide = lst_squ_harmonics( hfrc_obj, f ) hfrc_notide = lst_squ_harmonics( hfrc_obj, f ) [ hfrc_notide, hfrc_tide ] = lst_squ_harmonics( hfrc_obj, f ) [ hfrc_notide, hfrc_tide, AUs, theta_Us, AVs, theta_Vs ] = ... lst_squ_harmonics( hfrc_obj, f ) hfrc_notide = lst_squ_harmonics( hfrc_obj, f, AUs, theta_Us, ... AVs, theta_Vs ) [ hfrc_notide, hfrc_tide ] = lst_squ_harmonics( hfrc_obj, f, AUs, ... theta_Us, AVs, theta_Vs ) where f is an arbitrary length row vector of tidal frequencies in cycles/day, hfrc_notide is the detided hfrc object, hfrc_tide is the tidal part of the hfrc object, AUs is a [ n x gridPts ] matrix, where n is the number of tidal harmonics removed, with the final AU_i's mentioned above. Similarly for theta_Us, AVs, theta_Vs. All angles are returned in radians. Note that the last two forms allow you to give the A's and theta's, assuming they were calculated at some prior time with another time series (using the same grid), and have those components removed from the data. Note that this function will not perform tidal removal for any grid points for which less than 1 percent of the data is present, or for which there are less than 5 good points. NOTE that this function removes the mean from the data before performing the detiding (using the HFRC/polyfit function). The resulting detided HFRC object, however, contains this mean. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% $Id: lst_squ_harmonics.m,v 1.2 2003-04-02 00:56:07 dmk Exp $ Copyright (C) 2001 David M. Kaplan Licence: GPL %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

- end END - basic end method for HFRC objects.
- gooddata GOODDATA - returns a matrix of good data in object.
- length LENGTH - returns number of times in HFRC object.
- polyfit POLYFIT - Polynomial fitting for HFRC objects.
- polyval POLYVAL - HFRC method for polyval function
- size SIZE - returns [ (num times), (num gridpts) ].

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