Not enough input arguments

can anyone help me with this error?

Error in diva (line 25) Not enough input arguments.

function divF=diva(F,coords)
%find the analytical divergence of a given symbolic 3D vector function F 
% coords = 'car'/'cyl'/'sph'
% Copyleft: Won Y. Yang, [e-mail], CAU for academic use only 
if nargin<2, coords='ca'; end 
% Cartesian coordinate system by default switch lower(coords(1:2)) 
% Depending on which coordinate system to use

% Depending on which coordinate system to use
switch lower(coords(1:2)) 
    case 'cy' 
        syms r ph z; 
        coord = 'cylindrical'; 
        divF  = diff(r*F(1),r)/r + ...
                diff(F(2),ph)/r + ...
                diff(F(3),z); %(2.4.4b)
    case 'sp' 
        syms r th ph; coord='spherical';
        divF = diff(r^2*F(1),r)/r^2 + ...
               diff(F(2)*sin(th),th)/r/sin(th) + ...
               diff(F(3),ph)/r/sin(th); %(2.4.4c)
    otherwise  % coords ='ca'
      syms x y z; 
      coord='Cartesian';
      divF = diff(F(1),x) + ...
             diff(F(2),y) + ...
             diff(F(3),z); %(2.4.4a)
end

if nargout<1
    fprintf(['Div(F) in ' coord ' coordinate is']); 
    pretty(simplify(DivF)) 
end

Answer 1

[Walter Roberson]

You would get that error if you are passing in a function handle as the first parameter, and the function handle requires more than one parameter.

The code expects that the first parameter is either an array of 3 symbolic expressions, or else that it is a numeric array, or else it is a function handle with one parameter.