updating docstrings in pca
@@ -71,10 +71,12 @@ def pca(cube, angle_list, cube_ref=None, scale_list=None, ncomp=1,
number of PCs extracted from ``cube`` itself. If ``ncomp`` is a float
in the interval (0, 1] then it corresponds to the desired cumulative
explained variance ratio (the corresponding number of components is
- estimated). If ``ncomp`` is a tuple, then it corresponds to an
- interval of PCs in which final residual frames are computed. If
- ``source_xy`` is not None, then the S/Ns (mean value in a 1xFWHM
- circular aperture) of the given (X,Y) coordinates are computed.
+ estimated). If ``ncomp`` is a tuple of two integers, then it
+ corresponds to an interval of PCs in which final residual frames are
+ computed (optionally, if a tuple of 3 integers is passed, the third
+ value is the step). When``source_xy`` is not None, then the S/Ns
+ (mean value in a 1xFWHM circular aperture) of the given
+ (X,Y) coordinates are computed.
* ADI+RDI (``cube`` and ``cube_ref`` are 3d arrays): ``ncomp`` is the
number of PCs obtained from ``cube_ref``. If ``ncomp`` is a tuple,
