David Goodmanson

Last seen: Today | Active since 2012

Statistics

All

Content Feed

Answered
Explanation for a function within xcorr
Hi big, rather than puzzle this out in place, it seemed easier to look at the output of the function for the first hundred valu...

1 día ago | 0

Answered
Got wrong normal vector
Hi AC, You were quite right in your suspicions of the 3d plot, which looks fishy. You might call this a configuration control ...

1 día ago | 0

Answered
fft vs nufft- scaling
Hi Nathan, In the fft case you are dividing by N = 1500 and multiplying by 2. For nufft you aren't doing that. Hence the fact...

8 días ago | 0

| accepted

Answered
Why I got the dominant frequency as 1/time when I running fft?
Hi CS, here is an example, first with 800 points, then 400 points. The frequency scale is constructed differently in each one ...

16 días ago | 0

Answered
finding the orthogonal vectors for a series of vectors
Hi Pouya, Here is another method, somewhat related to Bruno's a = 2*rand(1000,3)-1; m1 = tril(ones(3,3)) -triu(ones(3,3)) ...

20 días ago | 1

Answered
spline for corner object
HI Mehri, try sorting by angle around a point in the center: x0 = 350; y0 = 325; theta = atan2(y-y0,x-x0); [~,ind] = sort(t...

20 días ago | 1

Answered
I want to solve this couple differential where the dot represent the derivative with respect to t/tp, where tp = 30E-9, is my code for solving this is correct? ?
Hi Sahil, Since the constants are all of order 10^-3 to 10^3 or so, it's evident that normalized units are in play. So you hav...

21 días ago | 0

Answered
Write a vectorial function from a scalar function
Hi Giuseppi, it looks like you intend, in this case, f = @(z,y) z.^2 + y^2 Here .^ gives the element-by-element square of z, ...

21 días ago | 0

Answered
What is the use case for ifft's trailing zero padding? Why is that the default?
Hi Kevin. Zeropaddinig has consequences. It also has its uses, but sometimes the results are unexpected. First of all, whatev...

26 días ago | 1

Answered
Why is it giving me undefined function for the slope field?
Hello Brenda, As an alternative to figuring out how to get that code up and running, or as a comparison, you can run your own c...

alrededor de 1 mes ago | 0

Answered
How to code this quadratic minimization problem subject to a linear constraint?
Hi Armando/Bianca Suppose lambda is a 1x3 row vector. The code below is based on the fact that the solution abc (which is the ...

alrededor de 1 mes ago | 0

Answered
Interpolation of the values of points on the surface created by convex hull
Hi Jose/Nima, Suppose you have a triangle with vertex points p1, p2, p3, each of those defined by a column vector of their x,y,...

alrededor de 1 mes ago | 0

Answered
generate white gaussian noise
Hi HL, Since white gaussian noise is just random draws from a normal distribution, you don't really need some toolbox or other,...

alrededor de 2 meses ago | 0

| accepted

Answered
Signal compensation of Time signal via FFT and cable loss frequency spectrum
Hi Michael, Although the Nyquist frequency is N/(2*delta_t), you have to consider both positive and negative frequencies. Assu...

alrededor de 2 meses ago | 0

Answered
calculation code of PSD using fft
Hi DK, Since you are after power spectral density, and not the spectrum of the linear quantity fft(x), this means the square of...

alrededor de 2 meses ago | 0

Answered
precision of double variables
Hi Arda, you pretty much answered the question by mentioning precision. Most floating point numbers are not represented exactl...

alrededor de 2 meses ago | 1

Answered
My code is giving only one solution to a function although there are two solutions, what can I do to get all the solutions?
Hi JN, syms x; assume(x,'positive') and proceed as before for the second one. It is not a great idea to use 'roots' as the n...

alrededor de 2 meses ago | 1

| accepted

Answered
plotting T-U diagram using XSteam
Hi Aldan, the code is running through all the values, but it's not saving any of them. You need to do something like m = 220;...

alrededor de 2 meses ago | 1

| accepted

Answered
I want to highlight the curve of intersection of the sphare and the plane x+y+z=0 by a thick blue curve. How to do that?
Hi Atom, Your code doesn't work because if you multiply out X2^2 + Y2^2 + Z2^2, you don't get R^2. So that arc is not on the s...

2 meses ago | 0

| accepted

Answered
How can I change this explicit method code to the implicit method code?
Hi MC I am not sure what is meant by 'implicit method', and while numerical methods are good, there is also the exact expressio...

2 meses ago | 0

Answered
How to plot the magnitude and the phase of this function f(1/z)=(0.5 + 000i)*z^(−1 )+ (0.2500 − 0.4330i)*z^(−2) + (−0.2500 − 0.4330i)*z^(−3)?
Hello Aisha, technically this equation should read f(z)=(0.5 + 000i)*z.^(−1 )+ (0.2500 − 0.4330i)*z.^(−2) + (−0.2500 − 0.4330i...

3 meses ago | 0

| accepted

Answered
How to Plot Ramsey Phase Plane
HI ec, There are a couple of issues here. First, the cdot expression lacks a dot, should be k.^(alpha-1). Second, the grid ...

3 meses ago | 0

| accepted

Answered
How the plot of the phase of the complex function look likes BY USING THE MATLAB?
Hi Aisha, Taking the second part first, a phase angle can be either positive or negative. The Matlab angle function uses the u...

3 meses ago | 0

| accepted

Answered
Analytical solution for 1D heat equation
Hi Dominick, you have the sum of two sine terms for the boundary condition, sin(x) and (1/10) sin(10x). So consider a general ...

3 meses ago | 0

| accepted

Answered
Why is 0 and 30 1/2?
Hi Alexander; This occurs because heaviside(-.3:.1:.3) ans = 0 0 0 0.5000 1.0000 1.0000 1.0000 ...

3 meses ago | 0

Answered
Difference between numerical and analytical solution of ode?
Hi IG, Here is an almost-analytical solution for x0 and x1 (which are called x and y respectively). It's analytic for x, uses ...

4 meses ago | 0

Answered
I want to plot an implicit equation
Hi mohd, This is not really an implicit equation since Vgs appears only once, by itself, on the lhs. So you can take all the o...

4 meses ago | 1

Answered
Circular Cross Correlation 2D Using FFT
Hi Ziv, yes, it works similarly. m = 5; n = 6; q = 4; A = randi(m,n,q); B = randi(m,n,q); C = zeros(size(A)); for j = 1:...

4 meses ago | 0

Answered
How to get coefficients for second degree polynomial with only two given boundary conditions (means with two equations but with three coefficients)?
Hi Ankit, x = [ 0 1 2 3]; E = [0 1 4.5 10.5]; c = polyfit(x,E,2) % fit a quadratic E1 = polyval(c,x) figure(1) plot(x,...

4 meses ago | 0

Answered
Is there any way to plot values that are exponent multiples of 10 as colorbar directly without having to take their log
Hi Mathan, The colorbars cover the same range in each case, but It's still apples and oranges. Consider the value 1e6 In log sp...

4 meses ago | 1

| accepted

David Goodmanson