Very important. Help :( Please :(

Record 30 seconds of your voice and repeat this process 20 times(20 sample functions)

1. you have to sample each function at each sec. Record the amplitudes at each sampled time in a separate vector and save it for final results(you suppose to have 20 vectors, each has 30 samples), these vectors are the sample functions of the random process. Then find the mean of those amplitudes Ax, and then plot this mean vs. time (time mean of sample functions). Finally calculate E[Ax]
2. take the first sample of each vector in step 1 and name this vector X1. This vector will have 20 samples. Repeat this step for X2,X3,..,X20(these are statistical random variables). X2 vector will be created by taking the second sample of each vector in step 1, and so on for all random variables. Calculate the average each Xi vector and sketch the averages vs. the number of random variable i.(statistical mean)

i've recorded my voice and converted the files into .wav, i dont know much about matlab. help :(

Answer 1

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/8026-best-way-s-to-master-matlab

http://www.mathworks.com/help/matlab/ref/for.html

http://www.mathworks.com/help/matlab/learn_matlab/array-indexing.html

Now why was this so important that I had to delay calling my mother on Christmas?? Because that's what "very important" means, that the person who reads it has to give it higher importance than anything that can be postponed.

http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency

[Matt J]

Better hope your mother's not reading this. She might wonder the same. ;)

[Mira Hamdan]

I'm sorry if i bothered you, this is so important because it's an assignment with 10 marks, the dr. didnt care that i didnt take matlab course yet, and still want it by Sunday :(

[Image Analyst]

Well I didn't answer until today, and had time to call Walter's mother yesterday, and she was thrilled to hear from me. I let her know Walter's call would be delayed because he was working on a project of top national priority.

So, Mira, what do you get for the return arguments from wavread():

[y, Fs, nbits, opts] = wavread(filename)

You need to know what Fs is to sample every 1 second. For example if Fs is 44,000 times per second, you need to sample every 44,000'th element.

[Walter Roberson]

[Mira Hamdan]

Image Analyst, the thing is i don't know anything about matlab, i'm taking the course next semester, and the professor don't care if i took the course or not he want the answer of the question or ill fail, i tried tutorials and stuff, but i didn't reach the level that i can solve this problem, can you ?

[Walter Roberson]

When I went to university, I failed three courses, and also had to retake one course to raise my mark. Failing that many courses turned out to limit my options, but it was not the end of my career.

The failures were a mix of limitations of my abilities (some of the courses), with my not having put in the months of necessary work (some of the courses.) The failures did not come about due to leaving something to the last minute and then expecting someone else to solve the problem for me.

Sometimes it takes failing a course to learn to plan and prioritize.

I would like to say that I learned my lesson and made sure to go to all of my classes, but that would not be entirely honest. I still had problems with some of my early morning classes (years later we realized there were medical reasons involved.) But the reasons were within me, my responsibility.

[John D'Errico]

Mira - Walter was very nice and answered your question. That you are now in a hurry is your problem, as Walter points out, due to your poor time management skills.

Answer 2

[Jan]

Dear Mira,

What kind of help do you expect? You cannot get your homework solved in this forum. Of course your teacher knows this forum also and recognizes the problem. And if you post a solution written by someone else, a single question about one line of the code will be enough to reveal, that you have cheated. In my university this is sufficient to become exmatriculated.

The only feasible answer is to suggest, to fail this course this time, because you simply do not have enough knowledge now to pass it. This forum cannot change this simple rule by any magic knowledge transfer.

But even if you realize, that your chances to solve the problem is small this year, you can start now. Read the links Walter has suggested. After the Getting Started chapters, you have enough information to write some code. Then try to solve some parts of your problem and ask specific questions here. This would not be cheating, but only an "expanded documentation".

[Walter Roberson]

But mostly: we respond more thoroughly to people who show evidence of having put in effort. When someone posts indicating what it is they do not understand, we respond with explanations that allow the person to move on and complete the work themselves. When someone just posts a copy of an assignment and not much more, we tell them to write a better question. It is the difference between tutoring (which we do) and doing someone's homework for them (which we do not do.)

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

[Matt J]

The only feasible answer is to suggest, to fail this course this time, because you simply do not have enough knowledge now to pass it.

Or, drop the course, if that's allowed this late in the semester. Then retake it once you have the pre-requisites.