56 total contributions since 2014

Vibration and Signal processing tutorials at http://www.mechanicalvibration.com

Answered

could u give me weiner program to remove audio noise

Did you try typing "Wiener filter matlab" into google first? There are all kinds of examples out there. Why don't you try that ...

could u give me weiner program to remove audio noise

Did you try typing "Wiener filter matlab" into google first? There are all kinds of examples out there. Why don't you try that ...

4 years ago | 0

Answered

Store tensor history into multidimensional array

As far as I am aware, it is not possible to do what you want in matlab. There is no such thing as a 3-dimensional array literal...

Store tensor history into multidimensional array

As far as I am aware, it is not possible to do what you want in matlab. There is no such thing as a 3-dimensional array literal...

4 years ago | 0

Answered

Can you help me out on making the BER vs SNR plot ?

Not 100% sure of the final answer here, but based on your statement that you are only getting 1 star on the graph, I assume that...

Can you help me out on making the BER vs SNR plot ?

Not 100% sure of the final answer here, but based on your statement that you are only getting 1 star on the graph, I assume that...

4 years ago | 0

Answered

retrieving the impulse response of a function using freqz (not impz)

I suspect your problem is that the system you are trying to study is unstable. i.e. the pole lies outside the unit circle, so t...

retrieving the impulse response of a function using freqz (not impz)

I suspect your problem is that the system you are trying to study is unstable. i.e. the pole lies outside the unit circle, so t...

4 years ago | 0

Answered

Faulty result on contour map

Not 100% sure what you mean by "some values are false", but I suspect that you've just transposed x and y axis. Does a = ...

Faulty result on contour map

Not 100% sure what you mean by "some values are false", but I suspect that you've just transposed x and y axis. Does a = ...

4 years ago | 0

Answered

Error with if elseif statements

In matlab, strings are arrays of characters. Two strings with different lengths have different array dimensions. e.g. 'dog'...

Error with if elseif statements

In matlab, strings are arrays of characters. Two strings with different lengths have different array dimensions. e.g. 'dog'...

4 years ago | 0

Answered

How do I set counter = to a value when it is a persistent variable so if i reinitialize it each time through a loop it loses it purpose?

I'm not sure if I understand the question. Here is my guess at what you are asking. If this isn't it, please restate the quest...

How do I set counter = to a value when it is a persistent variable so if i reinitialize it each time through a loop it loses it purpose?

I'm not sure if I understand the question. Here is my guess at what you are asking. If this isn't it, please restate the quest...

4 years ago | 0

Answered

How to use anonymous functions and fsolve to find initial conditions given final conditions (projectile motion)

So it looks like you are integrating an ODE numerically. Starting from a set initial conditions, you are doing a simple time in...

How to use anonymous functions and fsolve to find initial conditions given final conditions (projectile motion)

So it looks like you are integrating an ODE numerically. Starting from a set initial conditions, you are doing a simple time in...

4 years ago | 1

Answered

How to save a huge matrix efficiently?

If you have enough memory and are using a 64 bit version of matlab, using load() to load the entire matrix into memory will be q...

How to save a huge matrix efficiently?

If you have enough memory and are using a 64 bit version of matlab, using load() to load the entire matrix into memory will be q...

4 years ago | 0

Answered

Using interp1 multiple times to find a root : interp1 on a matrix without loops. Using interp1 multiple times for different values of query points without loops.

My first question here would be, are you pre-allocating root? i.e. do you have root = zeros(a,b,c) before your loop? If not, t...

Using interp1 multiple times to find a root : interp1 on a matrix without loops. Using interp1 multiple times for different values of query points without loops.

My first question here would be, are you pre-allocating root? i.e. do you have root = zeros(a,b,c) before your loop? If not, t...

4 years ago | 0

Answered

how to plot a unit step function

Do you want to do this numerically or symbollically? With the symbolic math toolbox, the heaviside() function is a unit step....

how to plot a unit step function

Do you want to do this numerically or symbollically? With the symbolic math toolbox, the heaviside() function is a unit step....

4 years ago | 0

| accepted

Answered

The code does not return the unwrapped phase. Why?

Not 100% sure I have the whole answer, but here's part of it. Look at these two lines side by side: %by first sequentially...

The code does not return the unwrapped phase. Why?

Not 100% sure I have the whole answer, but here's part of it. Look at these two lines side by side: %by first sequentially...

4 years ago | 1

Answered

Divide image into 3x3 pixels?

Depends. First, define "small" and "big". Do you mean it's okay for 10x10 but too slow for 1000x1000? Or does big mean 100,00...

Divide image into 3x3 pixels?

Depends. First, define "small" and "big". Do you mean it's okay for 10x10 but too slow for 1000x1000? Or does big mean 100,00...

4 years ago | 0

Answered

how to make table of ip address numbers

strsplit() will split up the strings for you. Then use sprintf() to make the formatting https://www.mathworks.com/help/matla...

how to make table of ip address numbers

strsplit() will split up the strings for you. Then use sprintf() to make the formatting https://www.mathworks.com/help/matla...

4 years ago | 0

Answered

While loop not working

I see two issues with your code: 1) By virtue of the fact that you have "while j <9" at the top, this implies that you expect...

While loop not working

I see two issues with your code: 1) By virtue of the fact that you have "while j <9" at the top, this implies that you expect...

4 years ago | 0

Answered

How to round (or convert) an array to integer?

ceil() should work to round up to the nearest integer

How to round (or convert) an array to integer?

ceil() should work to round up to the nearest integer

4 years ago | 1

Answered

Round to specified decimal number?

this thread looks appropriate: http://www.mathworks.com/matlabcentral/answers/14495-rounding-elements-in-array-to-nearest-0-2...

Round to specified decimal number?

this thread looks appropriate: http://www.mathworks.com/matlabcentral/answers/14495-rounding-elements-in-array-to-nearest-0-2...

4 years ago | 0

| accepted

Answered

ploting in for loop

"there is something wrong" is pretty vague, so I'm totally guessing at what your problem is. But this seems like a reasonable gu...

ploting in for loop

"there is something wrong" is pretty vague, so I'm totally guessing at what your problem is. But this seems like a reasonable gu...

4 years ago | 0

Answered

Why do I get this error: A(I): index out of bounds; value 2 out of bound 1 (line 13)

Because the very first time the while statement's condition is checked, n=2, and x is a vector that has 1 element. You are aski...

Why do I get this error: A(I): index out of bounds; value 2 out of bound 1 (line 13)

Because the very first time the while statement's condition is checked, n=2, and x is a vector that has 1 element. You are aski...

4 years ago | 0

Answered

How to determine a frequency that contains 90% of the power of the signal?

1) create a power spectrum (i.e. using the results of fft()). I'm assuming you know how to do this, if not just ask 2) create...

How to determine a frequency that contains 90% of the power of the signal?

1) create a power spectrum (i.e. using the results of fft()). I'm assuming you know how to do this, if not just ask 2) create...

4 years ago | 0

| accepted

Answered

sinewave generation:how generatea sine wave

t=0:0.001:1; freq = 10; signal = sin( freq * 2 * pi * t); plot(t, signal);

sinewave generation:how generatea sine wave

t=0:0.001:1; freq = 10; signal = sin( freq * 2 * pi * t); plot(t, signal);

4 years ago | 0

| accepted

Answered

HELP with creating matrix for Jacobi and Gauss-Seidel method problem!!

the brute force approach would be something like this. for i = 1:80 for j = 1:80 if (i==j) a(i,j) =...

HELP with creating matrix for Jacobi and Gauss-Seidel method problem!!

the brute force approach would be something like this. for i = 1:80 for j = 1:80 if (i==j) a(i,j) =...

4 years ago | 0

Answered

I want to copy the rows of G1 to G2 in inner for loop but error occurs , please help

the first time through the loops, k = 15. but size(G1) is 11x16. So the first time you are effectively doing G2(o,:) = G1(1...

I want to copy the rows of G1 to G2 in inner for loop but error occurs , please help

the first time through the loops, k = 15. but size(G1) is 11x16. So the first time you are effectively doing G2(o,:) = G1(1...

4 years ago | 0

Answered

simulating a poker game

You've got a good start. Here's a few comments 1) Instead of using randsample() and then finding and removing elements from t...

simulating a poker game

You've got a good start. Here's a few comments 1) Instead of using randsample() and then finding and removing elements from t...

4 years ago | 3

| accepted

Answered

How to plot spectrogram in Matlab using one-year length data with the sampling rate of 50 Hz?

if you don't really need 50 Hz resolution, then use decimate() to make the vector length smaller. If you really do need 50 Hz...

How to plot spectrogram in Matlab using one-year length data with the sampling rate of 50 Hz?

if you don't really need 50 Hz resolution, then use decimate() to make the vector length smaller. If you really do need 50 Hz...

4 years ago | 0

Answered

How to use fft2 and find spatial wavenumbers (kx & ky) ?

First, you need to reshape your data so that it is 10000x5x5 instead of 10000x25 ("reshape" command could help here). Then, a...

How to use fft2 and find spatial wavenumbers (kx & ky) ?

First, you need to reshape your data so that it is 10000x5x5 instead of 10000x25 ("reshape" command could help here). Then, a...

4 years ago | 1

Answered

I need to sum the values around the perimeter of a matrix, is there sum function in matlab

For your second sum, instead of sum(A(y,1:1:y)) think you wanted sum(A(x,1:1:y))

I need to sum the values around the perimeter of a matrix, is there sum function in matlab

For your second sum, instead of sum(A(y,1:1:y)) think you wanted sum(A(x,1:1:y))

4 years ago | 0

Answered

Plot double Fourier series in MATLAB

I think your problem is this line A=4*(-1)^(m+n)*(sin(m.*x)*sin(n.*y))/(m*n); from the way you have written it, it looks l...

Plot double Fourier series in MATLAB

I think your problem is this line A=4*(-1)^(m+n)*(sin(m.*x)*sin(n.*y))/(m*n); from the way you have written it, it looks l...

4 years ago | 0

Answered

Question on designing a filter to remove noise from a audio signal

step 1: analyze the signal and see if you can determine what frequencies are to be kept and what frequencies are to be discarded...

Question on designing a filter to remove noise from a audio signal

step 1: analyze the signal and see if you can determine what frequencies are to be kept and what frequencies are to be discarded...

4 years ago | 0

| accepted

Answered

2 signals to 1 channel ? use FFT

assuming that t is a vector containing time intervals, and that F1 and F2 are frequencies, and A1 and A2 are amplitudes, then I ...

2 signals to 1 channel ? use FFT

assuming that t is a vector containing time intervals, and that F1 and F2 are frequencies, and A1 and A2 are amplitudes, then I ...

4 years ago | 0