I want to iterate through each value of matrix through loop

Parameters2; % loads parameter values from parameters.m

ch=0.5; % changing factor

VAll = [rx rx*(1-ch) rx*(1+ch); %V(1:,)

 ax ax*(1-ch) ax*(1+ch);       %V(2:,)

       ry ry*(1-ch) ry*(1+ch);       %V(3:,)

       ay ay*(1-ch) ay*(1+ch);       %V(4:,)

       dx0 dx0*(1-ch) dx0*(1+ch);    %V(5:,)

       dy0 dy0*(1-ch) dy0*(1+ch);    %V(6:,)

       dx1 dx1*(1-ch) dx1*(1+ch);    %V(7:,) 

       dy1 dy1*(1-ch) dy1*(1+ch);    %V(8:,)

       cx cx*(1-ch) cx*(1+ch);       %V(9:,)

       cy cy*(1-ch) cy*(1+ch);       %V(10:,)

       ea ea*(1-ch) ea*(1+ch);       %V(11:,)

       es es*(1-ch) es*(1+ch);       %V(12:,)

       rs rs*(1-ch) rs*(1+ch);       %V(13:,)

       rya rya*(1-ch) rya*(1+ch);     %V(14:,)

      ryq ryq*(1-ch) ryq*(1+ch);     %V(15:,)

       rm rm*(1-ch) rm*(1+ch);        %V(16:,)

       A A*(1-ch) A*(1+ch)];          %V(17:,)

   dx1 =VAll(7,2);%or any of the above parameter

pars = [rx ax ry ay dx0 dy0 dx1 dy1 cx cy ea es rs rya ryq rm A k];

%% Initial values

Init = [x0I, x1I, y0I, y1I, aI, sI, yqI, xmI];

%% Solve ODE's the usual way

options = odeset('RelTol',1e-4,'AbsTol',1e-8); % Tolerances

[ts, cs] = ode15s(@Cancer_eqs,tspan,Init,options,pars); % Solve ODE's

save results.mat ts cs;

% %% Figures

Driver_Cancer_Figures

[Jan]

Your code is hard to read. Please remove the empty lines and use the "{} Code" button to apply a proper format. The description of your problem is lean an we have to guess, which variable you are talking of. If the code is not readable in addition, answering gets harder than necessary.