function G = rayxgridfB(F, transla, val)%------------------------------------------------------------------------------% Multiplies gridfunction F with element of stencil given by its value% val and its position transla.% Excess area is filled by extension of boundaryvalues.%% Design and implementation by:% Dr. Paul M. de Zeeuw <Paul.de.Zeeuw@cwi.nl>  http://homepages.cwi.nl/~pauldz/% Last Revision: July 13, 2001.% Copyright 1999-2002 Stichting CWI, Amsterdam%------------------------------------------------------------------------------o=[0 0];if ~all(size(o) == size(transla))  error(' rayxgridfB - unexpected dimensions of transla ')endif val == 0  G = zeros(size(F));elseif val == 1  G = moveLRB(moveUDB(F, -transla(1)), -transla(2));else  G = val * moveLRB(moveUDB(F, -transla(1)), -transla(2));end%------------------------------------------------------------------------------