Mercurial > hg > smallbox
view util/ksvd utils/collincomb.m @ 210:f12a476a4977 luisf_dev
Added help comments to SMALL_two_step_DL.m
author | bmailhe |
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date | Wed, 21 Mar 2012 17:25:40 +0000 |
parents | c3eca463202d |
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%COLLINCOMB Linear combination of matrix columns. % Y = COLLINCOMB(A,COLS,X) computes a linear combination of the columns of % the matrix A. The column indices are specified in the vector COLS, and % the correspoinding coefficients are specified in the vector X. The % vectors COLS and X must be of the same length. % % The call Y = COLLINCOMB(A,COLS,X) is essentially equivalent to % % Y = A(:,COLS)*X . % % However, it is implemented much more efficiently. % % Y = COLLINCOMB(A,ROWS,COLS,X) only works on the rows of A specified % in ROWS, returning a vector of length equal to ROWS. This call is % essentially equivalent to the command % % Y = A(ROWS,COLS)*X . % % See also ROWLINCOMB. % Ron Rubinstein % Computer Science Department % Technion, Haifa 32000 Israel % ronrubin@cs % % April 2009