Community Profile

photo

David Goodmanson


David Goodmanson

Last seen: 22 giorni fa Attivo dal 2012

Statistics

All
  • 36 Month Streak
  • Thankful Level 2
  • Revival Level 3
  • Guiding Light
  • Knowledgeable Level 5
  • First Answer
  • Solver

Visualizza badge

Content Feed

Visto da

Risposto
energy signal
Hi k.v. For a given real signal y(n) of length N, n = 1 to N, the power at any point n is y(n)^2, the average power P is Pave ...

27 giorni fa | 0

Risposto
How can I evaluate a complex definite integral?
Hi Valentin, It's not strictly necessary (see Paul's vpa solution) but it is advantageous to scale things properly before doing...

2 mesi fa | 0

Risposto
How to use sinc function
Hi Ricardo, while it might be nice to have the Signal Processing toolbox, you certainly don't need to buy any toolboxes to do t...

2 mesi fa | 0

Risposto
how to find concave angle between three points
Hi Eliska, One thing that does not seem to be mentioned so far is your use of the norm function on the determinant. That makes...

2 mesi fa | 0

Risposto
calculation error in hyperbolic function
one possibility: (tanh(-10))^2 ans = 1.0000 % correct although tanh(-(10)^2) % traveling parenthesis ans =...

2 mesi fa | 0

Risposto
Partial derivative with respect to x^2
Hi Yadavindu, df/d(x^2) = (df/dx) / (d(x^2)/dx) = (df/dx) / (2*x) which you can code up without the issue you are seeing.

2 mesi fa | 1

Risposto
Solving a system of Non-linear Equations with Complex numbers
Hellol Aravindhan, not solved by Matlab, but a bit of algebra shows that with x(1) = 2000*a x(2) = 2000*b x(3) = theta/5 t...

2 mesi fa | 0

Risposto
Increasing the caclulation speed while using loops
Hi Hamid, Hi Hamid, I have not speed checked this but it should be faster (the range in your example is different from the draw...

2 mesi fa | 2

| accettato

Risposto
How to introduce a phase shift to a existing vector
I assume that you are given the oscillatory function V in an array, with no accompanying array for the independent variable to s...

3 mesi fa | 0

Risposto
Average of random variables from two Poisson distributions?
Hi Jonne, I assume you want to look at the distribution for a period of one minute, whenever that might occur. As opposed to l...

3 mesi fa | 1

| accettato

Risposto
How to extrapolate a plot?
What is being fitted is T vs. C, with the idea of extrapolating to T=0. The C variable, C=log((A0-A1)./(A-A1)) contains A, wh...

3 mesi fa | 0

Risposto
z transfer function evaluates to inaccurate value near z=1
Hi Ashish, This function, ((1-1/z^2)/(1-1/z))^6 is identically equal to ((z+1)/z)^6 so you can just use that. And it does ...

3 mesi fa | 0

| accettato

Risposto
Why am I getting wrong spectrum applying FFT comparing with correct spectrum?
Hi Jiang, There are a couple of things going on here. The expression for FFT is not correct. Since you are taking the real pa...

3 mesi fa | 0

| accettato

Risposto
Solve system of equations with some knowns and unknowns in the same matrix
Hi Yusuf, I'm later on an answer (and losing the race more often, to the extent that there is a race, which to be honest there ...

3 mesi fa | 0

Risposto
How can I code a contour integral representation of cosine?
Hi Richard, this integral converges very slowly along the vertical path gamma-i*inf to gamma+i*inf. Convergence depends on wha...

3 mesi fa | 1

Risposto
reverse lookup table from vector multiplikation with unknown vectors
Hello Henning, Assuming that you want column vectors a and b such that their outer product C = a*b' is as close as possible to ...

3 mesi fa | 1

Risposto
How to define color on matrix figure
Hi Jan, the following method comes up with black not just for values that are exactly zero (I don't know how likely that might ...

4 mesi fa | 0

Risposto
Question using IFFT, try to transform continuous 1 from frequency in time domain
Hi Jan, In the secnd example the dirac value should be quite large, In fact it should be 3e5, the number of points, not half o...

4 mesi fa | 0

| accettato

Risposto
fminsearch for a function f(x,y) = x^4 -3xy+2y^2
Hi Ibraheem, While it's useful to find out about how to get fminsearch to cooperate, that's hardly necessary here. For the min...

4 mesi fa | 0

Risposto
Random numbers generation problem
Hi Daniel, here is one way, basically the sieve of Eratosthenes. nmax = 1000; a = randi(nmax,1,1e6); a(rem(a,2)== 0) = []; ...

4 mesi fa | 0

Risposto
different result of PCA function and my PCA
Hi Farshad, Each column vector in the cof matrix is arbitrary up to an overall constant of absolute value 1, which for the case...

4 mesi fa | 0

Risposto
My code is outputting very illogical answers for the second block (my second vector loop equation).
Hi Emily, No one seems to have mentioned that there are two independent solutions for the angle pair angle3 and angle4, since i...

4 mesi fa | 0

| accettato

Risposto
My code is outputting very illogical answers for the second block (my second vector loop equation).
Hi Emily, If VLE1 and VLE2 are lined up typographically, you have VLE1 = @(x0) [(R2.*cos(theta2_all(i)) + R3.*cos(x0(1)) -...

4 mesi fa | 0

Risposto
xcorr and finddelay giving erroneous results for offset sine waves
Hi James, This effect is due to a peculiarity in finding delays when your sample is cut off sharply at each end. The following...

4 mesi fa | 1

| accettato

Risposto
Would you tell me the code for Fisher Pearson skewness?
Hi Chris, y = rand(1,100); % some data m = mean(y); n = numel(y); scalc = (sum((y-m).^3)/n)/var(y,1)^(3/2) s = skewness...

4 mesi fa | 0

| accettato

Risposto
Why doesn't the kurtosis function work properly for complex numbers?
Hi Guillem, Both the standard deviation and the variance (std and var) work correctly for complex argument, so kurtosis appears...

4 mesi fa | 1

| accettato

Risposto
SIR model with recovered individuals may lose their immunity and become reinfected with the disease. But came with a failure about integration tolerances
Hi Julian, I have doubts about the equations, because with dq(1) = -S as you have, the equations are equivalent to S = -beta*S...

4 mesi fa | 0

Risposto
what does the positive and negative values concave mean?.
Hello Aisha, You are looking at a polynomial function of z, with two roots as you stated. To see what is going on, it helps to...

4 mesi fa | 0

| accettato

Risposto
Differentiate with Respect to Derivative
Hello Mitra, what version of Matlab are you running? Running your code in 2021b gives D1 = m*diff(x(t), t) as desir...

5 mesi fa | 1

Risposto
Huge difference between the result of fft function Matlab and analytical Fourier transform of the same function
Hi ST, Your frequency grid runs from -5 to 5, which for an fft is -fs/2 to fs/2 (fs being the sampling frequency), so fs = ...

5 mesi fa | 0

Carica altro