Answered

How to create an average of 2 lines on a single graph

Hi Charley since the second half of the distance array has exactly the same values as the first half (only reversed), you can u...

How to create an average of 2 lines on a single graph

Hi Charley since the second half of the distance array has exactly the same values as the first half (only reversed), you can u...

2 months ago | 0

Answered

Euler Angles from Rotation Matrix

Hi Gregory, If you mean you want the form of the rotation martrix in terms of alpha,beta,gamma, that's just syms a b g R1 = [...

Euler Angles from Rotation Matrix

Hi Gregory, If you mean you want the form of the rotation martrix in terms of alpha,beta,gamma, that's just syms a b g R1 = [...

2 months ago | 1

| accepted

Answered

roots of the complex equation with one variables

Hello Varun, Your code gives for solutions b = 30.857 - 175.74i -94.032 - 211.56i 70.398 - 342.7...

roots of the complex equation with one variables

Hello Varun, Your code gives for solutions b = 30.857 - 175.74i -94.032 - 211.56i 70.398 - 342.7...

2 months ago | 0

Answered

multiple r values for multiple theta values

Hi Allan For an element-by-element calculation, use ./ and .* rather than / and * theta=[pi,3,2.8,2.5,2,pi/2,1.3,1.0,0.75...

multiple r values for multiple theta values

Hi Allan For an element-by-element calculation, use ./ and .* rather than / and * theta=[pi,3,2.8,2.5,2,pi/2,1.3,1.0,0.75...

2 months ago | 1

Answered

Modifying 'Bessel second-order ordinary differential equation' in matlab library.

Hi K^2, Picking kr as the argument, take a look at J(kr) and do the differentiations on d^2/dr^2 J(kr) + (1/r) d/dr(J(kr). Ta...

Modifying 'Bessel second-order ordinary differential equation' in matlab library.

Hi K^2, Picking kr as the argument, take a look at J(kr) and do the differentiations on d^2/dr^2 J(kr) + (1/r) d/dr(J(kr). Ta...

2 months ago | 0

| accepted

Answered

solving a system of 2nd order 2 ODE: output vector length not matching the initial condition vector length

Hi yosri, the reason this is happening is that the expression for dy/dt has four elements, but one of them contains diff(y(4)) ...

solving a system of 2nd order 2 ODE: output vector length not matching the initial condition vector length

Hi yosri, the reason this is happening is that the expression for dy/dt has four elements, but one of them contains diff(y(4)) ...

2 months ago | 0

Answered

Create a vector field

Hi ALvaro, The code below sets P=Q=0 to make the spacial dependence more clear. Rather than meshgridding the 1d velocity vecto...

Create a vector field

Hi ALvaro, The code below sets P=Q=0 to make the spacial dependence more clear. Rather than meshgridding the 1d velocity vecto...

2 months ago | 0

| accepted

Answered

how can i calculate z^2 distibution?

Hello JS By gaussian I assume you mean the normal distribution, mean 0, std deviation 'a' f(z) = N*exp(-(z/a)^2/2) with N =...

how can i calculate z^2 distibution?

Hello JS By gaussian I assume you mean the normal distribution, mean 0, std deviation 'a' f(z) = N*exp(-(z/a)^2/2) with N =...

2 months ago | 0

| accepted

Answered

Solve function returns expression in terms of z

Hello Ashmika, You do have a symbolic solution for h, which goes to show that symbolic solutions are not always the ideal. The...

Solve function returns expression in terms of z

Hello Ashmika, You do have a symbolic solution for h, which goes to show that symbolic solutions are not always the ideal. The...

2 months ago | 0

| accepted

Answered

How can I get randperm to return a permutation of a vector that has no entries at their original positions?

Hi Darcy, the methods I have seen here seem to involve trying randperm and rejecting the result if an element remains in the sa...

How can I get randperm to return a permutation of a vector that has no entries at their original positions?

Hi Darcy, the methods I have seen here seem to involve trying randperm and rejecting the result if an element remains in the sa...

2 months ago | 0

Answered

Imaginary numbers when solving ode (ode15s)

Hello YF, whenever unexpected complex quantities start appearing, it's time to look for the usual suspects, which tend to be ei...

Imaginary numbers when solving ode (ode15s)

Hello YF, whenever unexpected complex quantities start appearing, it's time to look for the usual suspects, which tend to be ei...

2 months ago | 0

| accepted

Answered

Q Factor is not same

Hello Abdullah be aware that what you are calling alpha is often called alpha/2, but I don't think that had anything to do with...

Q Factor is not same

Hello Abdullah be aware that what you are calling alpha is often called alpha/2, but I don't think that had anything to do with...

2 months ago | 1

| accepted

Answered

How does nanstd function process complex numbers

Hi Luciano I'm not sure what you are referrng to with " nanstd(C) returns a complex matrix with dimentions equal to C and rea...

How does nanstd function process complex numbers

Hi Luciano I'm not sure what you are referrng to with " nanstd(C) returns a complex matrix with dimentions equal to C and rea...

3 months ago | 0

Answered

Power calculation from Voltage and current waveforms

Hi Stefano, The biggest issue is that when using trapz, you have not taken into account the width of the time steps when doing ...

Power calculation from Voltage and current waveforms

Hi Stefano, The biggest issue is that when using trapz, you have not taken into account the width of the time steps when doing ...

3 months ago | 0

Answered

FFT and Parseval's Theorem

Hi Chen, Here are a couple of ways. Since the time function fills up the entire time window (as opposed to being some kind of ...

FFT and Parseval's Theorem

Hi Chen, Here are a couple of ways. Since the time function fills up the entire time window (as opposed to being some kind of ...

3 months ago | 1

Answered

In the sine wave source is the formula that links samples per period and sample time correct? It says: Samples per period = 2*pi / (Frequency * Sample time), but I believe it should be Samples per period = Sample time / Frequency.

Hello Ilaria, I believe it is neither of those. Rather it is what is in the PNG with the 2pi crossed out: samples/period = 1/...

In the sine wave source is the formula that links samples per period and sample time correct? It says: Samples per period = 2*pi / (Frequency * Sample time), but I believe it should be Samples per period = Sample time / Frequency.

Hello Ilaria, I believe it is neither of those. Rather it is what is in the PNG with the 2pi crossed out: samples/period = 1/...

3 months ago | 0

Answered

Need help with this integral ? what is opstruct in integralcalc?

Hello HA I assume N is defined further on up since Matlab was not complaining about that. Try fun_2=@(t)(ones(size(t))*N); a...

Need help with this integral ? what is opstruct in integralcalc?

Hello HA I assume N is defined further on up since Matlab was not complaining about that. Try fun_2=@(t)(ones(size(t))*N); a...

3 months ago | 0

Answered

How to obtain the coordinate of the maximum value in the Cross ambiguity function

Hi John, Not having the phased array system toolbox I don't know how the plot axes are oriented, but I think one of the two pos...

How to obtain the coordinate of the maximum value in the Cross ambiguity function

Hi John, Not having the phased array system toolbox I don't know how the plot axes are oriented, but I think one of the two pos...

3 months ago | 0

Answered

solving ode equation using ode45

Hi nadeeshani, UPDATED ANSWER This is a speculative answer, but perhaps you did not take the square root when you calculated t...

solving ode equation using ode45

Hi nadeeshani, UPDATED ANSWER This is a speculative answer, but perhaps you did not take the square root when you calculated t...

3 months ago | 0

Answered

Why am I only getting partial streamlines.

Hi Boris, the problem is the line sy = sx./sx which creates a vector of ones for sy. Then every streamline originates at the h...

Why am I only getting partial streamlines.

Hi Boris, the problem is the line sy = sx./sx which creates a vector of ones for sy. Then every streamline originates at the h...

3 months ago | 0

Answered

Non-Integer For-Loop

Hi Christopher for h = 0:.1:1 works, although with the interval expressed in floating point, you have to be careful. for ...

Non-Integer For-Loop

Hi Christopher for h = 0:.1:1 works, although with the interval expressed in floating point, you have to be careful. for ...

3 months ago | 1

Answered

Why is dsolve solution halved from real answer?

Hi Miles, One of your conditions is dy/dt = 0 which is iffy, since there is a dirac delta function at the origin and you are no...

Why is dsolve solution halved from real answer?

Hi Miles, One of your conditions is dy/dt = 0 which is iffy, since there is a dirac delta function at the origin and you are no...

3 months ago | 4

Answered

error in computing atanh

Hello Francisco, The imaginary part is i*pi/2, so the two answers are a+i*pi/2 and a-i*pi/2, where a is real. Both answers are...

error in computing atanh

Hello Francisco, The imaginary part is i*pi/2, so the two answers are a+i*pi/2 and a-i*pi/2, where a is real. Both answers are...

3 months ago | 1

| accepted

Answered

Significance of Nyquist frequency and Maximum frequency THD computation for FFT analysis

Hi Alsher, you don't show the horizontal frequency scale but I believe that the very small peaks have spacing 5 Hz, there are 1...

Significance of Nyquist frequency and Maximum frequency THD computation for FFT analysis

Hi Alsher, you don't show the horizontal frequency scale but I believe that the very small peaks have spacing 5 Hz, there are 1...

3 months ago | 0

| accepted

Answered

How to calculate error of trapz() function?

Hi Emil, Although there are uncertainties, you can draw some conclusions by using reasonable assumptions. First, you have to b...

How to calculate error of trapz() function?

Hi Emil, Although there are uncertainties, you can draw some conclusions by using reasonable assumptions. First, you have to b...

3 months ago | 0

Answered

How do I prevent overwriting of matrix elements?

Hi Domantas This is just a provisional answer since I am not sure exactly what you are trying to do, but statements like H(1:...

How do I prevent overwriting of matrix elements?

Hi Domantas This is just a provisional answer since I am not sure exactly what you are trying to do, but statements like H(1:...

3 months ago | 0

| accepted

Answered

How do I use acot(x) as a continuous function in matlab?

Hi Michael, I believe that 1/2 - (1/pi)*atan(x) fills the bill. It's the same as (1/pi)*acot(x) for x>0 and is continuous, w...

How do I use acot(x) as a continuous function in matlab?

Hi Michael, I believe that 1/2 - (1/pi)*atan(x) fills the bill. It's the same as (1/pi)*acot(x) for x>0 and is continuous, w...

3 months ago | 1

| accepted

Answered

3D Plot of particle trajectory in E and B field

Hi Lujain, After setting v = [0 1 1] to provide some initial z velocity, figure(2) plot3(X(:,1),X(:,2),X(:,3)) grid on and ...

3D Plot of particle trajectory in E and B field

Hi Lujain, After setting v = [0 1 1] to provide some initial z velocity, figure(2) plot3(X(:,1),X(:,2),X(:,3)) grid on and ...

3 months ago | 0

| accepted

Answered

How to Find the Rotation Matrix?

Hi ercan, MODIFIED First of all, for a rotation matrix the two known columns have to be an orthonormal pair, meaning that ther...

How to Find the Rotation Matrix?

Hi ercan, MODIFIED First of all, for a rotation matrix the two known columns have to be an orthonormal pair, meaning that ther...

3 months ago | 2

| accepted

Answered

Waveform not staring at origin

Hi SA, If you temporarily set c0 = 0 you obtain a nice trapezoidal wave of amplitude 1 that oscillates about y = 0 and has a me...

Waveform not staring at origin

Hi SA, If you temporarily set c0 = 0 you obtain a nice trapezoidal wave of amplitude 1 that oscillates about y = 0 and has a me...

3 months ago | 0