Not enough input arguments.

Working with A_new and trying to implement it into the R function but keep getting an error for not enough input arguments.

%Values
GMs = 1.3271244*10^20; %Nm^2/kg
GMe = GMs/332946;
x_1 = -124850219*1000; %km -> m
x_2 = -78506090*1000; %km-> m
v_1 = 15.857131*1000; %km/s-> m/s
v_2 = -25.712187*1000; %km/s->m/s
%astroids
x_1a =-154965574*1000;%km/s->m/s
x_2a = -249465245*1000;%km/s->m/s
v_1a= 24.723504*1000;%km/s->m/s
v_2a = 2.645546*1000;%km/s->m/s
% a anonymous function
x_i = [x_1,x_2];
% x_2D = sqrt(x_1^2+x_2^2); %2D- x
% x_2D = vecnorm(x_i);
% A = @(x) [((-GMs/(x_2D^3))*x_1) ; (-GMs/(x_2D^3))*x_2];
A = @(x) ( -GMs ./ (vecnorm(x).^3)) * x; %Acceleration
A_new= @(x,x_e) (( -GMs ./ (vecnorm(x).^3)) * x) - (GMe ./ (vecnorm(x-x_e).^3)*(x-x_e)); %acceleration with earths gravity
% a_i = [a_1 a_2]
a_i = A(x_i)';
% below is the values I got and they match the values given
a_1 = 5.17; %mm/s^2 ->0.0052 m/s^2
a_2 = 3.25; %mm/s^2 -> 0.0032m/s^2
%b combine arrays into 2x2 matrix
v_i = [v_1,v_2];
v_ia =[v_1a,v_2a];
%u = [x_1, v_1; x_2, v_2]; %Earth
u=[x_1, v_1; x_2, v_2; x_1a, v_1a; x_2a,v_2a];%astroid + Earth
R = @(u) [u(1:2,2),A(u(1:2,1));u(3:4,2),A_new(u(3:4,1))];%based on solution from class
%R = @(u) [u(:,2),A(u(:,1))]; for part b
%R = @(u) [u(1:2,2),A(u(1:2,1));u(3:4,2),A(u(3:4,1))]; for f and g
% R = @(u) [v_i A(x)];
%c Motion of earth over 366 days
% Explicit Euler Scheme
t = 0;
dt = 100;
matrix_u=u(:,1);
while t(end)< 31622400
    t(end+1)=t(end)+dt;
    %u=expliciteuler(u,dt,R);
    u=rungekutta(u,dt,R); %e Runge-Kutta Scheme
    matrix_u(:,end+1)=u(:,1);
end

Unrecognized function or variable 'rungekutta'.

figure(1)
plot(matrix_u(1,:),matrix_u(2,:),'g',matrix_u(3,:),matrix_u(4,:),'r') %d plot explicit Euler and e Rungekutta
grid on
legend('Earths Orbit', 'Astroid Orbit')
%g distance between earth and astroid orbit
d = vecnorm( [matrix_u(1, : ) ; matrix_u( 2, : ) ] - [ matrix_u( 3 , : ) ; matrix_u( 4 , : ) ]  );
d_o= d*(1/332946);
%d(1:50) % to recall some of the distances 
%y=min(d)
[min_value, min_index] = min(d)
[min_value, min_index] = min(d_o)

[Torsten]

Could you include the missing function ?

Answer 1

[Sulaymon Eshkabilov]

In your A_new, you should have vecnorm known in A_new. If vecnorm() is a norm of a vector x that you are trying to compute, then you had better use this syntax while calling: A_new , e.g.:

A_new= @(x,x_e) (( -GMs ./ (norm(x).^3)) * x) - (GMe ./ (norm(x-x_e).^3)*(x-x_e)); 

[Walter Roberson]

I do not understand what you are saying about vecnorm ?

I am not sure if you are saying that vecnorm is not a Mathworks function? Because it is vecnorm .

Or are you saying that it has been used incorrectly ??