receiving error when code is correct on matlab onramp Project - Stellar Motion II task 4?

my code: 

for v = 1:7
    s = spectra(:,v);
    if speed(v)<= 0
        plot(lambda,s,"--")
    else
       plot(lambda,s,"--","LineWidth",3) 
    end
    hold on
end
hold off

It says incorrect for "Did you make a plot with seven line?" and I did? How can I fix this?

[Umair]

same problem

Answer 1

[Devaraj Malladad]

i used below code got result all Pass

if not working, do multiple times of run and logout and login the cource . it amy work

for v = 1:7
    s = spectra(:,v);
    1<=1
    if speed(v) <=0
        plot(lambda,s,"--")
    end
        hold on
end

Answer 2

[Abhishek Chakram]

Hi Alyssa,

I understand that you are facing issue in completing the Project - Steller Motion II, task 4.

To my understanding, in the 4th task you are just required to plot graph with LineWidth 3, you need not to specify the type of line (here, dashed line)

You can refer to the following code:

for v = 1:7
    s = spectra(:,v);
    if speed(v) <= 0
        plot(lambda,s,'--');
    else
        plot(lambda,s,'LineWidth',3);
    end
    hold on;
end
hold off;

[Umair]

this dosent fix the problem

[Sai Krishna Kiriti]

I t says in incorrect

[David]

I'm currently facing similar problem. Were you able to solve it?

Answer 3

[Mohammed amine]

EXERCICE

Modifiez la ligne 2 du script. Supprimez (:,2) pour calculer la vitesse de toutes les étoiles.

[Mohammed amine]

Projet finalProjet - Mouvement stellaire II tasks 2-4

[Ismail]

s = spectra(:,2)
[sHa,idx] = min(spectra)
lambdaHa = lambda(idx)
z = (lambdaHa/656.28) - 1
speed = z*299792.458 

I cannot go further beyond this point.  Many thanks.

Answer 4

[David]

Use the code snippet below in [Task 2-4]

for c = 1:7
    s = spectra(:,c);
    if speed(c) <= 0
        loglog(lambda, s, "--")
    else
        loglog(lambda, s, "LineWidth", 3)
    end
    hold on
end
hold off
xlabel('Wavelength') % Adding label for x-axis
ylabel('Intensity') % Adding label for y-axis

Answer 5

[Prachi]

for v= 1:7
    
    s = spectra(:,v);

    if speed(v) <=0
        plot(lambda,s,"--")
    else
        plot(lambda,s,LineWidth=3) 
    end
    hold on
end
hold off