Getting an Error in input arguments

error is

>>Error using ga (line 342)

Not enough input arguments.

Caused by: Failure in initial user-supplied nonlinear constraint function evaluation.

I guess it is because of the way I have defined functions. I have three function files.My functions are defined as :FIRST FUNCTION IS DEFINED AS

    function Dos=Databeam(x)
% Units: KN & m
m=2;n=3;
x=mapvariablesbeam(x);

SECOND FUNCTION IS DEFINED AS

    function x = mapvariablesbeam(x)

THIRD FUNCTION IS DEFINED AS

    function [c, ceq] = ga_beamconstraints(x,Dos)
% Problem parameters
Lb=2;  %in m
deltaMax =Lb/325 ; % Maximum end deflection in m
sigmaMax =130e3 ; % Maximum stress in each section of the beam in kN/m
x = mapvariablesbeam(x);
% Constraints on the stress 
momax=Dos.momax;

momax variable is created in first function file and I need to access it in this function file so I have used Dos.momax

[Image Analyst]

The first function does not return a variable called Dos, so that will be a problem. Also, you did not include the function called ga(). What is the name of the main function / m-file? and show us line 342 where your main function calls ga(). And of course attach ga().