@FUNCTION=periodogram
@SYNTAX=periodogram(ordinates,[filter,[abscissas,[interpolation,[number]]]])
@DESCRIPTION=
periodogram returns the periodogram of the data
as a one column matrix.
@ordinates are the ordinates of the data to interpolate.
@filter gives the window function to be used. Possible values are:
- 0: no filter (rectangular window);
- 1: Bartlett (triangular window);
- 2: Hahn (cosine window);
- 3: Welch (parabolic window);
@abscissas are the absicssas of the data to interpolate. If no
abscissa is given, it is supposed that the data absicssas are regularly
spaced. Otherwise, an interpolation method will be used to evaluate
regularly spaced data.
* Strings and empty cells in @abscissas and @ordinates are simply ignored.
@interpolation is the method to be used for the interpolation;
possible values are:
- 0: linear;
- 1: linear with averaging;
- 2: staircase;
- 3: staircase with averaging;
- 4: natural cubic spline;
- 5: natural cubic spline with averaging.
@number is the number of interpolated data to be used. If not given,
a default number is automatically evaluated.
