I have a function returning a 3x1 vector. I now want to plot three graphs for these three outputs.

Here is my function:

function [ T] = inlamning1( F, m, l )
%Ax = b, A = alla skalärer framför T1,T2,T3 i de tre ekvationerna.
%T = [T1, T2, T3]
%b = skalärerna mg och F

A = [cosd(30), cosd(30), cosd(45); -1*sind(30), sind(30), sind(45); 10*cosd(30), 0, -1*cosd(45).*l];
b = [F*cosd(45)+ m*9.81; -1*F*sind(45) ; -1*F*cosd(45)*10];
T = A\b;

I now want to draw three diffrent graphs showing how T1, T2 and T3 differs for different values of l (l = linspace(5,10))

How can i do that?

[John D'Errico]

Please use the code formatting button to make your code readable. Select the block of code, then click on the {}Code button.

Next, it is a terrible idea to use the lower case letter l as a variable name. Far too often it will be confused with the number 1, thus 1 versus l. Of course, if your goal is to obfuscate your code completely, making it impossible to read and debug ever, even for you, then use only variable names composed of a jumble of the letters O and l, and the numbers 0 and 1.

Answer 1

[Ced]

Hi

Maybe I'm missing something, but you want to run the function for each value of linspace(5,10) and plot them? Then that's exactly what you should do.

Your script "run_inlamning1.m" (or whichever name you prefer) might then look something like:

    % define parameters
    F = 1;
    m = 1;
    Ivec = linspace(5,10);
    N = length(Ivec); % 100 by default

    % initialize matrix to save results
    T_all = zeros(3,N)

    % compute all values
    for i = 1:N
        T_all(:,i) = inlamning1(F,m,Ivec(i));
    end

    % plot
    plot(Ivec,T_all);
    xlabel('Ivec');
    legend('T1','T2','T3')

In case you're not aware of this: You can get help for all matlab functions by typing "help functionname", e.g. "help plot" directly in matlab. Or "doc plot" for a more extensive help with examples, etc.

Cheers

EDIT Note: if you want T1, T2, T3 to be in different plots, just type "figure" before each plot so the previous one does not get overwritten. You may also want to have a look at "subplot", e.g. subplot(1,3,1) would let you have the three plots side-by-side.

PS: Use the "Code" button when you want to insert code, otherwise it's hardly legible.

[Karim El Ghamrawi]

Thank you very much :) This is my first question so i am new to all this, but now i know until the next time :)