How to find the point on the root locus with a certain damping in Octave

[Deesse23]

So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true?

As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.

[FlatAssembler]

So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true?

As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.

We were also taught that in our high-school chemistry classes. But in our university physics classes, we were taught that real science uses error margins in inputs, and that it claculates the error margins of the results using the partial derivatives of the formulas.

[Jackalope]

So, allegedly, for the gain of 0.723288, the damping is equal to 0.689481 (very close to the required damping of 0.7), and the frequency is 0.104 rad/sec. How do I check whether that's true?

As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.

I think you might be on to something.

[Deesse23]

As early as my first semesters at university i figured (and was told by my profs) that anyone calculating 6 digit numbers trying to solve a 2 digit number problem has no idea what he is doing.

I think you might be on to something.

Shall i ask him if the damping value he was supposed to look for was rather 0.707 instead of 0.7? What do you think?

[FlatAssembler]

I am not certain whether the frequency for some complex root is indeed equal to the absolute value of the imaginary part of that root (as I have programmed into my program) or if it is equal to the absolute value of that root. I think it is equal to the absolute value of the imaginary part, because how can a root that's lying on a real axis (so that damping is equal to one) have a frequency? If the damping is equal to one, then the step response does not resemble a sinusoid, to have some frequency.

[Deesse23]

I am not certain whether the frequency for some complex root is indeed equal to the absolute value of the imaginary part of that root (as I have programmed into my program) or if it is equal to the absolute value of that root. I think it is equal to the absolute value of the imaginary part, because how can a root that's lying on a real axis (so that damping is equal to one) have a frequency? If the damping is equal to one, then the step response does not resemble a sinusoid, to have some frequency.

What did i say!?: You dont have an idea what you are doing, but your answer to "please look for 0.7" has six digits.

[FlatAssembler]

About a week ago, I had an opportunity to try this out in MatLab at the university, and MatLab prints results by orders of magnitude different from the results that the C++ program I've written prints. MatLab prints that for the damping of 0.701, the gain is 43.9 and the frequency is 0.141 rad/s. It is way more likely I got something wrong in my C++ program (though I'd like to know what) than in MatLab.

[BrianSoddingBoru4]

@FlatAssembler

Have you learned nothing from recent events? Nothing at all?

Boru

[FlatAssembler]

@FlatAssembler

Have you learned nothing from recent events? Nothing at all?

Boru

What recent events?

[arewethereyet]

You obviously learned nothing from your week-long time out. Perhaps you can learn from a longer, if not permanent, break from the forum.