fastslope

 calculate slope (deg) using GRADIENT function

0001 function grad = fastslope(dem,X,Y)
0002 % calculate slope (deg) using GRADIENT function
0003 dx=abs(X(2)-X(1));  % get cell spacing in x and y direction
0004 dy=abs(Y(2)-Y(1));  % from coordinate vectors
0005 [fx,fy] = gradient(dem,dx,dy); % uses simple, unweighted gradient of immediate neighbours
0006 [asp,grad]=cart2pol(fy,fx); % convert to carthesian coordinates
0007 grad=atand(grad); %steepest slope