Answered

Constructing an FFT-like result array.

HI betz, All of the following applies if the time domain waveform is REAL For a N point fft, N even: (a) point 1 is the four...

Constructing an FFT-like result array.

HI betz, All of the following applies if the time domain waveform is REAL For a N point fft, N even: (a) point 1 is the four...

7 days ago | 1

| accepted

Answered

Equation of Motion is Blowing Up

HI Samuel, I won't have access to Matlab for a few days so this needs to be verified, but I believe that in the last line of th...

Equation of Motion is Blowing Up

HI Samuel, I won't have access to Matlab for a few days so this needs to be verified, but I believe that in the last line of th...

10 days ago | 0

Answered

transfer functions arithmetic - is it distributive?

Hi Kapil, The second expression is merely the first expression multiplied by (z-1)/(z-1). So the two are equivalent, with the s...

transfer functions arithmetic - is it distributive?

Hi Kapil, The second expression is merely the first expression multiplied by (z-1)/(z-1). So the two are equivalent, with the s...

10 days ago | 0

Answered

How can I re-write an anonymous function into a standard function?

Hi Jesus, [ CORRECTED to include a minus sign ] function [returns,variance] = MultiObjective(mu,C,w) returns = -mu'*w'; ...

How can I re-write an anonymous function into a standard function?

Hi Jesus, [ CORRECTED to include a minus sign ] function [returns,variance] = MultiObjective(mu,C,w) returns = -mu'*w'; ...

12 days ago | 0

| accepted

Answered

I'm trying to ad a condition to an equation

Hi Xavier, I don't think your original function is overcomplicated at all. It's straightforward code that is self-commenting, ...

I'm trying to ad a condition to an equation

Hi Xavier, I don't think your original function is overcomplicated at all. It's straightforward code that is self-commenting, ...

14 days ago | 1

Answered

Cholesky Decomposition Column-Wise Algorithm Implementation

Hi J, I added to the code in your last comment by including the obvious missing 'for' statements, etc. After that, it's pretty...

Cholesky Decomposition Column-Wise Algorithm Implementation

Hi J, I added to the code in your last comment by including the obvious missing 'for' statements, etc. After that, it's pretty...

2 months ago | 1

| accepted

Answered

scientific notation in each element

Hi c^2, try "format short g" beforehand. Things stay that way until further notice. To go back to the default you can use ...

scientific notation in each element

Hi c^2, try "format short g" beforehand. Things stay that way until further notice. To go back to the default you can use ...

2 months ago | 0

| accepted

Answered

FFT of ON OFF signal

Hi imran, you appear to be pretty close on this. The code below uses ftshift to put f = 0 at the middle of the freq array, and...

FFT of ON OFF signal

Hi imran, you appear to be pretty close on this. The code below uses ftshift to put f = 0 at the middle of the freq array, and...

2 months ago | 0

| accepted

Answered

Centered FFT & DFT: cannot devise required phase shift vector(s).

Hi Peter, here are some phase shifts. I shortened up some of the variable names to make it easier (for me, anyway) to follow w...

Centered FFT & DFT: cannot devise required phase shift vector(s).

Hi Peter, here are some phase shifts. I shortened up some of the variable names to make it easier (for me, anyway) to follow w...

2 months ago | 1

| accepted

Answered

Why is 1/ones(3,1) OK while 1/ones(1,3) is not OK?

Hi Yuki, In the expression x = 1/ones(3,1) multiplying both sides on the right by ones(3,1) gives x*ones(3,1) = 1. The row ve...

Why is 1/ones(3,1) OK while 1/ones(1,3) is not OK?

Hi Yuki, In the expression x = 1/ones(3,1) multiplying both sides on the right by ones(3,1) gives x*ones(3,1) = 1. The row ve...

2 months ago | 2

| accepted

Answered

Bivariate Normal Distribution different for expression and mvnpdf()

Hello Aishwarya, The problem here is that the array x is 2x31 and does not have every possible combination of an element of X1 ...

Bivariate Normal Distribution different for expression and mvnpdf()

Hello Aishwarya, The problem here is that the array x is 2x31 and does not have every possible combination of an element of X1 ...

2 months ago | 2

| accepted

Answered

How do you find the approximate interval that displays the solution?

Hello Isabel, I believe the idea here is that when lambda is large enough, the expression for Tb gets increasingly close to Tb_...

How do you find the approximate interval that displays the solution?

Hello Isabel, I believe the idea here is that when lambda is large enough, the expression for Tb gets increasingly close to Tb_...

2 months ago | 0

Answered

ODE45 to solve a system of two coupled 2nd order ODEs

Hi Ricardo, I am inferring that you have the following system with fixed points S: S---k1---M---k2---M---k1---S Then eqn 1 is...

ODE45 to solve a system of two coupled 2nd order ODEs

Hi Ricardo, I am inferring that you have the following system with fixed points S: S---k1---M---k2---M---k1---S Then eqn 1 is...

3 months ago | 0

| accepted

Answered

How to element wise exponential of a matrix

Hi Titas, dy = Columns 1 through 10 15.7800 31.5600 47.3400 63.1200 78.9000 94.6800 110.4600 126.2400 142.0200...

How to element wise exponential of a matrix

Hi Titas, dy = Columns 1 through 10 15.7800 31.5600 47.3400 63.1200 78.9000 94.6800 110.4600 126.2400 142.0200...

3 months ago | 1

| accepted

Answered

Anttena Paterns radiation patterns

Hello MT, The basic issue is setting phi_3db to degrees, but there may also be a problem with the basic definition of phi_3db (...

Anttena Paterns radiation patterns

Hello MT, The basic issue is setting phi_3db to degrees, but there may also be a problem with the basic definition of phi_3db (...

3 months ago | 0

| accepted

Answered

"Fminunc cannot continue" Error with gamma function

Hi Yasin, You can use the gammaln function which is tailor made for this situation.

"Fminunc cannot continue" Error with gamma function

Hi Yasin, You can use the gammaln function which is tailor made for this situation.

3 months ago | 1

| accepted

Answered

How can I find a p-value when dealing with a weighted sum of chi-square distributions?

HI Michael, Since this is a weighted sum instead of a weighted mixture (as I erroneously assumed), the calculation will be alon...

How can I find a p-value when dealing with a weighted sum of chi-square distributions?

HI Michael, Since this is a weighted sum instead of a weighted mixture (as I erroneously assumed), the calculation will be alon...

3 months ago | 0

Answered

Interpreting xcorr results compared to corrcoef

Hi Jonathan, For the input column vectors, corrcoeff subtracts the mean off of each one and normalizes each to be a unit vector...

Interpreting xcorr results compared to corrcoef

Hi Jonathan, For the input column vectors, corrcoeff subtracts the mean off of each one and normalizes each to be a unit vector...

3 months ago | 1

| accepted

Answered

How to generate matrices that satisfies constraints on sum of row elements and sum of column elements?

Hi sharadhi, Here is an example for 3x3, where all the row and column sums are 100 (looks like you edited the original question...

How to generate matrices that satisfies constraints on sum of row elements and sum of column elements?

Hi sharadhi, Here is an example for 3x3, where all the row and column sums are 100 (looks like you edited the original question...

3 months ago | 0

Answered

Cumulative distribution function of a function of a random variable

Hi Franziska, a = 1.2; x = .2 y = a*(1+x)*(2/(1+ (1+x)^(1/(a-1))))^(a-1) xx = (y/a)/(2-(y/a)^(1/(a-1)))^(a-1) -1 % ...

Cumulative distribution function of a function of a random variable

Hi Franziska, a = 1.2; x = .2 y = a*(1+x)*(2/(1+ (1+x)^(1/(a-1))))^(a-1) xx = (y/a)/(2-(y/a)^(1/(a-1)))^(a-1) -1 % ...

3 months ago | 0

| accepted

Answered

FFT interpolation using zero-padding and the Chirp Z-Transform for a single tone sinusoid

Hi Matt, I made one minor change at the beginning of your code, replacing the first four lines with M = 100; m = linspace(0,1...

FFT interpolation using zero-padding and the Chirp Z-Transform for a single tone sinusoid

Hi Matt, I made one minor change at the beginning of your code, replacing the first four lines with M = 100; m = linspace(0,1...

3 months ago | 0

| accepted

Answered

Fourier transform of table signal

Hello fima, It’s true that the amplitude is off, but frequency is a much more serious issue. The time domain plot shows that t...

Fourier transform of table signal

Hello fima, It’s true that the amplitude is off, but frequency is a much more serious issue. The time domain plot shows that t...

3 months ago | 0

Answered

fourier transform of exp

HI Hadimargo, A few modifications are necessary to make this work out. oo First, in the time domain the exponential function i...

fourier transform of exp

HI Hadimargo, A few modifications are necessary to make this work out. oo First, in the time domain the exponential function i...

3 months ago | 1

| accepted

Answered

Generate random numbers from a mixture distribution

Hi Thomas. I presume you mean something like the following. A uniform random variable is used to create an index that picks fr...

Generate random numbers from a mixture distribution

Hi Thomas. I presume you mean something like the following. A uniform random variable is used to create an index that picks fr...

4 months ago | 2

Answered

How to rotate the plot attached(Truncated Pyramid) to make its sides parallel to its Axis.

Hi adam, two lines become y(m)=R*sind(n+45); x(m)=R*cosd(n+45);

How to rotate the plot attached(Truncated Pyramid) to make its sides parallel to its Axis.

Hi adam, two lines become y(m)=R*sind(n+45); x(m)=R*cosd(n+45);

4 months ago | 0

| accepted

Answered

Trouble with MATLAB Triple Integral

Hi Goerge, The problem with the func([x,y,z]) approach is that there is too much expectation that [x,y,x] is 1x3. Once the int...

Trouble with MATLAB Triple Integral

Hi Goerge, The problem with the func([x,y,z]) approach is that there is too much expectation that [x,y,x] is 1x3. Once the int...

4 months ago | 0

| accepted

Answered

Linear interpolation with multiple values for each point

Hi Justin, If the problem is what I think it is, with d and e known, linear interpolation between o and p determined by a<d<b ...

Linear interpolation with multiple values for each point

Hi Justin, If the problem is what I think it is, with d and e known, linear interpolation between o and p determined by a<d<b ...

4 months ago | 0

Answered

Problem with the Color Bar

Hi Hans, try colormap(jet) colorbar by default this has 64 color levels (as does the default colormap, 'parula') and looks m...

Problem with the Color Bar

Hi Hans, try colormap(jet) colorbar by default this has 64 color levels (as does the default colormap, 'parula') and looks m...

4 months ago | 1

| accepted

Answered

Question about fft2(2D Fourier Transform) of a Gaussian function

Hi Zhu Li, A couple of things are going on here. First, there is the checkerboard pattern in the angle plot. I added an extra ...

Question about fft2(2D Fourier Transform) of a Gaussian function

Hi Zhu Li, A couple of things are going on here. First, there is the checkerboard pattern in the angle plot. I added an extra ...

4 months ago | 1

| accepted

Answered

The power sum of all frequencies seems that the half amount of the middle frequency power is not added. But the algorithm accords with the Parseval theorem. why?

Hi H^2, It helps that you are doing this for four frequencies rather than some crazy huge number of them. x = 1:4; N = length...

The power sum of all frequencies seems that the half amount of the middle frequency power is not added. But the algorithm accords with the Parseval theorem. why?

Hi H^2, It helps that you are doing this for four frequencies rather than some crazy huge number of them. x = 1:4; N = length...

4 months ago | 0

| accepted