How can I make this a callable function?

function [i,IS]=firststateupdate(N,P_ub,w1)
for i=1:N
         w1=randi([0,1],1);
         if IS(i)==2 && w1<P_ub
            IS(i)=1;
         end
end
end
Not enough input arguments.

Error in firststateupdate (line 2)
for i=1:N

[Steven Lord]

What happens when you try to call it like any other MATLAB function? How do you try to call it?

• Do you receive warning and/or error messages? If so the full and exact text of those messages (all the text displayed in orange and/or red in the Command Window) may be useful in determining what's going on and how to avoid the warning and/or error.
• Does it do something different than what you expected? If so, what did it do and what did you expect it to do?
• Did MATLAB crash? If so please send the crash log file (with a description of what you were running or doing in MATLAB when the crash occured) to Technical Support so we can investigate.

[BAILEY MCMASTER]

I updated with errors I'm getting in matlab. Sorry I dont know why it won't run normally.

[Torsten]

IS is an unset output argument in your function. This throws an error.

[i,IS] = firststateupdate(10,0.7,0.6)

Unrecognized function or variable 'IS'.

Error in solution>firststateupdate (line 6)
if IS(i)==2 && w1<P_ub

function [i,IS]=firststateupdate(N,P_ub,w1)
  for i=1:N
    w1=randi([0,1],1);
    if IS(i)==2 && w1<P_ub
        IS(i)=1;
    end
  end
end

[BAILEY MCMASTER]

So here is my project I'm trying to make this section of code its own function. I have it defined. How do I make this code its own callable function. The normal code works, but I'm trying to snip things into there own function. Hers my base code.

N=10; % number of integrins
L=100; % size of the domain 100nm
D=.01; % diffusion coefficient
dt=1; % time step
F=randi([1, 10],1); % force on the bond with a random number of 1 to 10
P_a=randi([0,1],1); % binding rate of a random number from 0 to 1
P_ub=1/(1.5*F); % unbinding rate based upon our previous values
Tmax=500; % max time
% Intialize our integrins
x=randi([0,360],N,1); % x-coordinates generated randomily for each integrin
y=randi([0,50],N,1); % y-coordinates generated for each 
state=ones(N,1); % Each integrin is set to an inactive state at 0
% our figure
figure;
axis([0 L 0 L]);
set(gca,'nextplot','replacechildren');
% position update
for t = 0:dt:Tmax
% colors for our integrin states
colors = repmat([1 0 0], N,1); % red for inactive state
colors(state == 2,:,:) = repmat([0 1 0],sum(state == 2),1);
% plotting our integrins
 scatter(x,y,50,colors,'filled');
 title(sprintf('Time=%.2f',t));
 drawnow;
     for i=1:N
         w=randi([0,1],1); 
         if state(i)==1
         dx=randi([-360,360],1);
         dy=randi([-50,50],1);
         x(i)=x(i)+dx;
         y(i)=y(i)+dy; 
         quiver(x(i),y(i))
         end 
     end
     x=mod(x,L);
     y=mod(y,L);
     for i=1:N
         w_1=randi([0,1],1);
         if w_1 < P_a && state(i)==1
             state(i)=2;
             
         end
     end
     for i=1:N
         w1=randi([0,1],1);
         if state(i)==2 && w1<P_ub
            state(i)=1;
        
         end
     end
    Displacement=sqrt((mean(x.^2))/N);
end

[Torsten]

Think about what the function is supposed to do.

This will automatically tell you which inputs are needed and which outputs are to be supplied.

Answer 1

[Animesh]

Hey BAILEY,

I understand that you are trying to create and call functions inside the script.

I tried implementing this at my end and it is working fine. I am attaching the modified base code below:

N=10; % number of integrins
L=100; % size of the domain 100nm
D=.01; % diffusion coefficient
dt=1; % time step
F=randi([1, 10],1); % force on the bond with a random number of 1 to 10
P_a=randi([0,1],1); % binding rate of a random number from 0 to 1
P_ub=1/(1.5*F); % unbinding rate based upon our previous values
Tmax=500; % max time
% Intialize our integrins
x=randi([0,360],N,1); % x-coordinates generated randomily for each integrin
y=randi([0,50],N,1); % y-coordinates generated for each 
state=ones(N,1); % Each integrin is set to an inactive state at 0
% our figure
figure;
axis([0 L 0 L]);
set(gca,'nextplot','replacechildren');
% position update
for t = 0:dt:Tmax
% colors for our integrin states
colors = repmat([1 0 0], N,1); % red for inactive state
colors(state == 2,:,:) = repmat([0 1 0],sum(state == 2),1);
% plotting our integrins
 scatter(x,y,50,colors,'filled');
 title(sprintf('Time=%.2f',t));
 drawnow;
     for i=1:N
         w=randi([0,1],1); 
         if state(i)==1
         dx=randi([-360,360],1);
         dy=randi([-50,50],1);
         x(i)=x(i)+dx;
         y(i)=y(i)+dy; 
         quiver(x(i),y(i))
         end 
     end
     x=mod(x,L);
     y=mod(y,L);
     for i=1:N
         w_1=randi([0,1],1);
         if w_1 < P_a && state(i)==1
             state(i)=2;
             
         end
     end

     state=firststateupdate(N,P_ub,state); % Function Call 

    Displacement=sqrt((mean(x.^2))/N);
end

Also refer the modified function ‘firststateupdate.m’ that you were trying to create below:

function [IS]=firststateupdate(N,P_ub,IS)
    for i=1:N
             w1=randi([0,1],1);
             if IS(i)==2 && w1<P_ub
                IS(i)=1;
             end
    end
end

NOTE: When working with functions, ensure that you include all the input arguments used while defining the function before yuo call it.

For more information on creating functions in MATLAB, consider going through the following link:

• https://in.mathworks.com/help/matlab/matlab_prog/create-functions-in-files.html
• https://in.mathworks.com/help/matlab/matlab_prog/local-functions-in-scripts.html

I hope this helps.