Problem 44934. Plot Damped Sinusoid

b-- and r*

I would rate it as an easy task to solve, but the problem description is a bit clumsy, for example m is a minimum return value, so I rated medium not for solving difficulty, but understanding description difficulty :)

the leading solution is incorrect...the minimum value of y does not correspond to a time value of 1, but corresponds to a value of 0.4887...plot the leading solution to confirm.

nice Problem- [m,pos] = min(X)

This solution previously submitted passes the tests but is incorrect as it does not find the associated t value for m.

not bad

you should be really careful about the description of the question, for example, i failed a few times for not notice i should use "m" to denotes the min.

This comment saved me a big headache. No idea what they wanted from m.

thanks a lot for the hint, it really matters

The test suite should also verify that the red dot has been placed correctly. In fact, even if the abscissa of the point in question is taken wrong, the wrong code is accepted as a solution.

There is a bug on the verification, the minimum value with the lowest size solution is not plotted at the correct time value.

function m = plot_cos(y, t)
[m,pos] = min(y);
plot(t,y,'b--',t(pos),m,'r*');

function m = plot_cos(y, t)
[m,idx]=min(y);
t_m=t(idx);
plot(y,t,'b--',m,t_m,'r*')
end

why doesn't it work? It gives the error "Check plotted data" but my data works just fine on my pc. Any ideas on why it doesn't accept my solution?

Just change the order in plotting, i.e,
plot(t,y,'b--',t_m,m,'r*')
since plot(x,y) is main function.
x->t and y->y

use hold on after first plot

I have submitted the code which is working exactly as required in matlab script but cody is not accepting my solution.Please help

Why is this program failing?
function m = plot_cos(y, t)
j = size(y);
k = zeros(1,j(2));
a = k - y;
b = max(a);
k = find(a==b);
m = -b;
plot(t,y,'--',t(k),m,'r*');
end

cool,didn't know the ''1,ans'',it's a great way to use this function.
but why "1", didn't understand

Maybe this test doesn't check XData so "1" is valid for the solution

assert(isequal([h.YData],[m, y]), 'Check plotted data')

Nice code

There seems to be a bug in the test suite. This is passed as a valid solution, although the minimum point is not correctly marked.

To give a correct result, line 3 should read:

plot(t,y,'b--',t(im),m,'r*');

absolutely, but the thing is how other peers were able to submit

Hi Ali, this is because the output m is expected to contain the minimum value of the input y, not a handle to the plot.
Hope that helps.

function m = plot_cos(y, t)
[m,idx]=min(y);
t_m=t(idx);
plot(t,y,'b--',t_m,m,'r*')
end

:-D

I have the same problem lol, and thanks for pointing out the blind spot!

the test syntax in line 5 is wrong

So we don't need to plot the graph?

That is correct. The problem description is one thing. The test suite is another. The test suite explicitly accommodates solutions that do not plot the graph. Since this took extra effort to incorporate into the test suite, I view my solution as fully within the scope and intent of this problem.

It works perfectly fine on PC.

Thanks Paresh. Your approach is a valid solution that the tests were not designed to evaluate previously. I have now modified the tests to pass this alternative approach. However, there are two other issues with this solution, which you will have to resolve: 1. The color 'b' expected for the line is not the same as the default blue color the MATLAB uses. 2. The output is expected to be the minimum value of y, not a handle to the plot.

I have also added appropriate messages for the tests. Thanks again!

why it is failing..i dont understand..it gives no indication why assertions have failed

Hi Asif, the output from the function is expected to be only the minimum value of vector y; whereas your code returns both - the minimum value of y and also the corresponding t. This is causing the last test to fail. I will modify the tests to make it clearer. You should pass the tests if you set m = ymin

thank u

Hey any chance i could get a little help with 44934 Plot Damped Sinusoid

I don't understand what is wrong. The output below states that the assertion failed on test 2, but it gives no indication of which assertion failed or what the cause was. I plotted this on my matlab and it produced the plot shown in the problem statement. Please clarify what the error is in my code.

Andrew, I suspect that this is failing the second test because the new plot lines are being plotted over the previous plot (from test 1). It is always a good practice to use 'hold off' (here and in MATLAB, generally) to stop plotting over old plots. Having said that, I will consider adding a 'figure' command to the tests, since Cody does not display the plots and it is difficult to debug this particular problem without seeing the plots.

Pooja, you were correct. Adding the hold off command to the end of the code allowed it to submit successfully. Thank you.