Unable to perform assignment because the left and right sides have a different number of elements.

Unable to perform assignment because the left and right sides have a different number of elements.

(line 93)

t_ar(step_counter)=t; % Add the current time to the time logclearvars

Does anyone know why I'm getting this error?

% Setup

t_max= 1200; % in s

k=0.01; % in s^-1

g_nr=2; % in molecules/s

t_nr=0; % in s

x_nr=5; % in molecules

step_counter=1;

% Perturbations

perturbation_magnitude=150; % in molecules

perturbation_time_400=400;% in s

perturbation_time_800=800;% in s

is_perturbation_400=0;

is_perturbation_800=0;

% Simulation of the non-regulated construct

t=0;

prod_rate=g_nr;

while t<t_max

deg_rate=k*x_nr(step_counter);

wait_time=-log(rand)/((prod_rate)+(deg_rate));

prob_prod=(prod_rate)/((prod_rate)+(deg_rate)); % Propensity of production

t=t+wait_time; % Update current time

step_counter=step_counter+1; % Update the number of steps (reactions) associated with the experiment.

t_nr(step_counter)=t; % Add the current time to the time log

if rand < prob_prod % Defines whether production takes place based on Monte Carlo method.

x_nr(step_counter)=x_nr(step_counter-1)+1; % Implements production

else

x_nr(step_counter)=x_nr(step_counter-1)-1; % Implements degradation

end

if t>perturbation_time_400 && is_perturbation_400==0

x_nr(step_counter)=x_nr(step_counter)+perturbation_magnitude;

is_perturbation_400=1;

end

if t > perturbation_time_800 && is_perturbation_800==0

x_nr(step_counter)=x_nr(step_counter)-perturbation_magnitude;

is_perturbation_800=1;

end

if t>t_max

t_nr(end)=[];

x_nr(end)=[];

end

end

close all

figure,

plot(t_nr,x_nr,'r','LineWidth',2)

hold on

% plot(x_nr,'b','LineWidth',2)

% legend('t_nr','x_nr')

% autoregulated construct

t_max= 1200; % in s

k=0.01; % in s^-1

step_counter=1;

t=0;

g_nr=2;

x_nr=5;

g_ar=4;

n_hill=8;

x_ar=5;

t_ar=0;

theta=(g_nr)/k;

% Perturbations

perturbation_magnitude=150; % in molecules

perturbation_time_400=400;% in s

perturbation_time_800=800;% in s

is_perturbation_400=0;

is_perturbation_800=0;

while t<t_max

prod_ratea=g_ar*((theta.^n_hill)./((theta.^n_hill)+(x_ar.^n_hill)));

deg_rate=k*x_ar(step_counter);

wait_time=-log(rand)./((prod_ratea)+(deg_rate));

prob_prod=prod_ratea/((prod_ratea)+(deg_rate)); % Propensity of production

t=t+wait_time; % Update current time

step_counter=step_counter+1; % Update the number of steps (reactions) associated with the experiment.

t_ar(step_counter)=t; % Add the current time to the time log

if rand < prob_prod % Defines whether production takes place based on Monte Carlo method.

x_ar(step_counter)=x_ar(step_counter-1)+1; % Implements production

else

x_ar(step_counter)=x_ar(step_counter-1)-1; % Implements degradation

end

if t>perturbation_time_400 && is_perturbation_400==0

x_ar(step_counter)=x_ar(step_counter)+perturbation_magnitude;

is_perturbation_400=1;

end

if t > perturbation_time_800 && is_perturbation_800==0

x_ar(step_counter)=x_ar(step_counter)-perturbation_magnitude;

is_perturbation_800=1;

end

if t>t_max

t_ar(end)=[];

x_ar(end)=[];

end

end

plot(t_ar,x_ar,'b','LineWidth',2)

% hold on

% plot(x_ar,'b','LineWidth',2)

legend('x_nr','x_ar')

Answer 1

[Image Analyst]

t is not a scalar then. Just put a breakpoint there and see what the size of t is.

t is

t =

0.326275650711335 0.326275650711493

which can't fit into a single array element.

[Jonathan Louie]

what does it mean that t is not scalar?

[Kevin Holly]

t is 2x1 and not 1x1

I changed the code below to fix the error, however the solution may be wrong. You will need to check to see if the correct algorithm was performed.

% Setup
t_max= 1200; % in s
k=0.01; % in s^-1 
g_nr=2; % in molecules/s
t_nr=0; % in s
x_nr=5; % in molecules
step_counter=1;
% Perturbations
perturbation_magnitude=150; % in molecules
perturbation_time_400=400;% in s
perturbation_time_800=800;% in s
is_perturbation_400=0;
is_perturbation_800=0;
% Simulation of the non-regulated construct
t=0; 
prod_rate=g_nr; 
while t<t_max
      
    deg_rate=k*x_nr(step_counter);
    wait_time=-log(rand)/((prod_rate)+(deg_rate));
    prob_prod=(prod_rate)/((prod_rate)+(deg_rate)); % Propensity of production
    
    t=t+wait_time; % Update current time
    step_counter=step_counter+1; % Update the number of steps (reactions) associated with the experiment.
    t_nr(step_counter)=t; % Add the current time to the time log
    if rand < prob_prod % Defines whether production takes place based on Monte Carlo method.
        x_nr(step_counter)=x_nr(step_counter-1)+1; % Implements production
    else
        x_nr(step_counter)=x_nr(step_counter-1)-1; % Implements degradation
    end
    if  t>perturbation_time_400 && is_perturbation_400==0
        x_nr(step_counter)=x_nr(step_counter)+perturbation_magnitude;
        is_perturbation_400=1;
    end
    
    if t > perturbation_time_800 && is_perturbation_800==0
        x_nr(step_counter)=x_nr(step_counter)-perturbation_magnitude;
        is_perturbation_800=1;
    end
           
    if t>t_max
        t_nr(end)=[];
        x_nr(end)=[];    
    end
 end
    close all
    figure,
        plot(t_nr,x_nr,'r','LineWidth',2)
        hold on
%         plot(x_nr,'b','LineWidth',2)
%         legend('t_nr','x_nr')
%  autoregulated construct
t_max= 1200; % in s
k=0.01; % in s^-1 
step_counter=1;
t=0; 
g_nr=2;
x_nr=5;
g_ar=4;
n_hill=8;
x_ar=5;
t_ar=[];
theta=(g_nr)/k;
% Perturbations
perturbation_magnitude=150; % in molecules
perturbation_time_400=400;% in s
perturbation_time_800=800;% in s
is_perturbation_400=0;
is_perturbation_800=0;
 while t<t_max
    prod_ratea=g_ar*((theta.^n_hill)./((theta.^n_hill)+(x_ar.^n_hill)));
    deg_rate=k*x_ar(step_counter);
    wait_time=-log(rand(1))./((prod_ratea)+(deg_rate));
    prob_prod=prod_ratea/((prod_ratea)+(deg_rate)); % Propensity of production
    
    t=t+wait_time(1); % Update current time
    step_counter=step_counter+1; % Update the number of steps (reactions) associated with the experiment.
    t_ar(step_counter)=t; % Add the current time to the time log
    if rand < prob_prod % Defines whether production takes place based on Monte Carlo method.
        x_ar(step_counter)=x_ar(step_counter-1)+1; % Implements production
    else
        x_ar(step_counter)=x_ar(step_counter-1)-1; % Implements degradation
    end
    if  t>perturbation_time_400 && is_perturbation_400==0
        x_ar(step_counter)=x_ar(step_counter)+perturbation_magnitude;
        is_perturbation_400=1;
    end
    
    if t > perturbation_time_800 && is_perturbation_800==0
        x_ar(step_counter)=x_ar(step_counter)-perturbation_magnitude;
        is_perturbation_800=1;
    end    
    if t>t_max
    t_ar(end)=[];
    x_ar(end)=[];
    end
end
        plot(t_ar,x_ar,'b','LineWidth',2) 
%         hold on
%         plot(x_ar,'b','LineWidth',2)
        legend('x_nr','x_ar')

[Jonathan Louie]

Thank you so much!