annotate util/ksvd utils/collincomb.m @ 247:ecce33192fcc tip

Added tag ver_2.1 for changeset cef4500b936f
author luisf <luis.figueira@eecs.qmul.ac.uk>
date Wed, 31 Oct 2012 12:24:44 +0000
parents c3eca463202d
children
rev   line source
idamnjanovic@70 1 %COLLINCOMB Linear combination of matrix columns.
idamnjanovic@70 2 % Y = COLLINCOMB(A,COLS,X) computes a linear combination of the columns of
idamnjanovic@70 3 % the matrix A. The column indices are specified in the vector COLS, and
idamnjanovic@70 4 % the correspoinding coefficients are specified in the vector X. The
idamnjanovic@70 5 % vectors COLS and X must be of the same length.
idamnjanovic@70 6 %
idamnjanovic@70 7 % The call Y = COLLINCOMB(A,COLS,X) is essentially equivalent to
idamnjanovic@70 8 %
idamnjanovic@70 9 % Y = A(:,COLS)*X .
idamnjanovic@70 10 %
idamnjanovic@70 11 % However, it is implemented much more efficiently.
idamnjanovic@70 12 %
idamnjanovic@70 13 % Y = COLLINCOMB(A,ROWS,COLS,X) only works on the rows of A specified
idamnjanovic@70 14 % in ROWS, returning a vector of length equal to ROWS. This call is
idamnjanovic@70 15 % essentially equivalent to the command
idamnjanovic@70 16 %
idamnjanovic@70 17 % Y = A(ROWS,COLS)*X .
idamnjanovic@70 18 %
idamnjanovic@70 19 % See also ROWLINCOMB.
idamnjanovic@70 20
idamnjanovic@70 21
idamnjanovic@70 22 % Ron Rubinstein
idamnjanovic@70 23 % Computer Science Department
idamnjanovic@70 24 % Technion, Haifa 32000 Israel
idamnjanovic@70 25 % ronrubin@cs
idamnjanovic@70 26 %
idamnjanovic@70 27 % April 2009