function val = dtint(A,R)% dtint.m Discrete-transform-based interpolation of a%         (1D) scalarfield object to a set of points within%         the range of the scalarfield's quadgrid object%%	INPUT parameters:%               A : a 1D scalarfield object %               R : one or more points%%	OUTPUT:%	        B : a double array%% Note: For the interpolation to work, A must be completely% defined (i.e., no NaN)Aval  = get(A,'val');Apd   = get(A,'pd');I = find(~(Aval > -realmax & Aval < realmax)); % returns indices of NaN elementsif prod(length(I)) > 0, error('A must be completely defined (no NaN)'), endgeomOld  = get(Apd,'geom');qpOld    = get(Apd,'qp');nameOld  = get(Apd,'name');Qinv     = get(Apd,'Qinv');if length(nameOld) >= 2   error('Not yet set up for higher-dimensional scalarfield objects')   endPrintExtrapolationWarning = 0;%%%%%%%%%%%%%%% 1D to 1D interpolation %%%%%%%%%%%%%%%if length(nameOld) == 1   [val,extrapflag] = ...       dtint(qpOld{1},Aval,R,Qinv{1},geomOld{1});   if extrapflag, PrintExtrapolationWarning = 1; end   endif PrintExtrapolationWarning      warning('Extrapolation produced NaN entries in output');      end