idamnjanovic@1: %ROWLINCOMB Linear combination of matrix rows.
idamnjanovic@1: %  Y = ROWLINCOMB(X,A,ROWS) computes a linear combination of the rows of
idamnjanovic@1: %  the matrix A. The row indices are specified in the vector ROWS, and the
idamnjanovic@1: %  correspoinding coefficients are specified in the vector X. The vectors
idamnjanovic@1: %  ROWS and X must be of the same length. The call Y = ROWLINCOMB(X,A,ROWS)
idamnjanovic@1: %  is essentially equivalent to the command
idamnjanovic@1: %
idamnjanovic@1: %         Y = X'*A(ROWS,:) .
idamnjanovic@1: %
idamnjanovic@1: %  However, it is implemented much more efficiently.
idamnjanovic@1: %
idamnjanovic@1: %  Y = ROWLINCOMB(X,A,ROWS,COLS) only works on the columns of A specified
idamnjanovic@1: %  in COLS, returning a vector of length equal to COLS. This call is
idamnjanovic@1: %  essentially equivalent to the command
idamnjanovic@1: %
idamnjanovic@1: %         Y = X'*A(ROWS,COLS) .
idamnjanovic@1: %
idamnjanovic@1: %  See also COLLINCOMB.
idamnjanovic@1: 
idamnjanovic@1: 
idamnjanovic@1: %  Ron Rubinstein
idamnjanovic@1: %  Computer Science Department
idamnjanovic@1: %  Technion, Haifa 32000 Israel
idamnjanovic@1: %  ronrubin@cs
idamnjanovic@1: %
idamnjanovic@1: %  April 2009