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How do I apply a gravitational gradient to this code? (particles in elastic collision)
Hi Alex If you don't need the details of the actual trajectory, the method is pretty simple. Modeling the asteroid as a sphere...
How do I apply a gravitational gradient to this code? (particles in elastic collision)
Hi Alex If you don't need the details of the actual trajectory, the method is pretty simple. Modeling the asteroid as a sphere...
4일 전 | 0
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How do I find the equation of points on a spline curve?
Hi Aiden, you have to remember that for each section of the spline, the polynomial is local to that section, i.e. the argument ...
How do I find the equation of points on a spline curve?
Hi Aiden, you have to remember that for each section of the spline, the polynomial is local to that section, i.e. the argument ...
13일 전 | 0
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When I use ode45 to solve a state space equation, the solution will be diverge. Interestingly, if I set the ma (which I've overstriked) to zero, the result will be converge.
Hi Z^2, It's not easy to say for sure without seeing the actual model, but I think there is a decent chance that your C matrix ...
When I use ode45 to solve a state space equation, the solution will be diverge. Interestingly, if I set the ma (which I've overstriked) to zero, the result will be converge.
Hi Z^2, It's not easy to say for sure without seeing the actual model, but I think there is a decent chance that your C matrix ...
14일 전 | 0
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Finding the Analytical Equation q(t) for an RLC Circuit Using Given V(t) Data
Hi Trais, The exact solution for q(t) involves integrating the voltage for times less than t. Let w = sqrt(-R^2/4L^2 + 1/LC) ...
Finding the Analytical Equation q(t) for an RLC Circuit Using Given V(t) Data
Hi Trais, The exact solution for q(t) involves integrating the voltage for times less than t. Let w = sqrt(-R^2/4L^2 + 1/LC) ...
18일 전 | 0
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Inverse fft doesn't match analytical formulation
Hi SW, There is a sign error in your transform pair, which should be 1/w^2 <--> -|x|/2 not 1/w^2 <--> |x|/2 As has been n...
Inverse fft doesn't match analytical formulation
Hi SW, There is a sign error in your transform pair, which should be 1/w^2 <--> -|x|/2 not 1/w^2 <--> |x|/2 As has been n...
24일 전 | 1
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why the voltage across a resistor with two different input DC source is the avg of the two different input DC voltage
Hi RAM, The 1 ohm resistor is quite a bit larger than the two .01 ohm resistors so in a first approximation the 1 ohm resistor ...
why the voltage across a resistor with two different input DC source is the avg of the two different input DC voltage
Hi RAM, The 1 ohm resistor is quite a bit larger than the two .01 ohm resistors so in a first approximation the 1 ohm resistor ...
대략 1개월 전 | 0
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INTEGARTION OF BESSELH function
Hi george, I don't know what the values of your parameters are, but it appears that the problem with Escat is that besselh(0,2...
INTEGARTION OF BESSELH function
Hi george, I don't know what the values of your parameters are, but it appears that the problem with Escat is that besselh(0,2...
대략 1개월 전 | 0
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No feasible solution found
Hi Preston, It seems likely that this is a planar structure with the diagonal elements having length sqrt(2). (If all th...
No feasible solution found
Hi Preston, It seems likely that this is a planar structure with the diagonal elements having length sqrt(2). (If all th...
대략 2개월 전 | 0
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2D Fourier transform- problems with the shift
Hi nathan, It is a bit more inconvenent but you can reconstruct using a shifted grid as you did. I kept that method in in the ...
2D Fourier transform- problems with the shift
Hi nathan, It is a bit more inconvenent but you can reconstruct using a shifted grid as you did. I kept that method in in the ...
대략 2개월 전 | 0
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How to find indices of resampled values from the indices of the original values?
Hello Mibang, Rather than snew = resample(s,fsnew,fs) I think it's safer to use [snew tnew] = resample(s,t,fsnew) because t...
How to find indices of resampled values from the indices of the original values?
Hello Mibang, Rather than snew = resample(s,fsnew,fs) I think it's safer to use [snew tnew] = resample(s,t,fsnew) because t...
2개월 전 | 1
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fft and ifft of signal seem to cause time reversal
Hi sgreess, I'm guessing your input signal is a column vector. In that case the command spectra = spectra' by Matlab conven...
fft and ifft of signal seem to cause time reversal
Hi sgreess, I'm guessing your input signal is a column vector. In that case the command spectra = spectra' by Matlab conven...
2개월 전 | 0
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How to fit this model with a Weibull distribution?
Hi MIchele, One possibility is that you are not fitting the correct statistical function to the data. The algebraic expression...
How to fit this model with a Weibull distribution?
Hi MIchele, One possibility is that you are not fitting the correct statistical function to the data. The algebraic expression...
3개월 전 | 0
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Problem with integration: there is a pole on a contour
Hi SB You can use the principal value for the integration,which is defined as (1/2) * [ (integral with path on one side of the...
Problem with integration: there is a pole on a contour
Hi SB You can use the principal value for the integration,which is defined as (1/2) * [ (integral with path on one side of the...
4개월 전 | 1
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Generalised solution to a n-order system of equations
HI Aden, Here is a method that produces, within 4.5 %, the experimental value a_1 = 2.518. The equation is (for simplicty n-1 ...
Generalised solution to a n-order system of equations
HI Aden, Here is a method that produces, within 4.5 %, the experimental value a_1 = 2.518. The equation is (for simplicty n-1 ...
4개월 전 | 1
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Solve more complex problems in matlab
HI OF, y(x) = (m-2)x^2 -3mx + (m+2) The domain of m where the two roots have opposite sign is a numerical question and I think...
Solve more complex problems in matlab
HI OF, y(x) = (m-2)x^2 -3mx + (m+2) The domain of m where the two roots have opposite sign is a numerical question and I think...
4개월 전 | 0
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How can I scale and plot the graph according to the formula I use?
Hi Zaref, One thing for sure about eq.(19) in the attachment is that eps0 can't be in the numerator. eps_m is dimensionless (a...
How can I scale and plot the graph according to the formula I use?
Hi Zaref, One thing for sure about eq.(19) in the attachment is that eps0 can't be in the numerator. eps_m is dimensionless (a...
4개월 전 | 0
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Plotting Complex Functions.
Hello Sudharsana, Do you mean f(t) = exp(-ar/(twC))*exp(-ai/(twC)) or f(t) = exp(-ar/(twC))*exp(-i*ai/(twC)) ...
Plotting Complex Functions.
Hello Sudharsana, Do you mean f(t) = exp(-ar/(twC))*exp(-ai/(twC)) or f(t) = exp(-ar/(twC))*exp(-i*ai/(twC)) ...
4개월 전 | 0
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How to apply orientation constraints between two rigid bodies
Hi Aiden, because of the parallelism there are only two degrees of freedom here (assuming that one pivot point is the hole nea...
How to apply orientation constraints between two rigid bodies
Hi Aiden, because of the parallelism there are only two degrees of freedom here (assuming that one pivot point is the hole nea...
4개월 전 | 1
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How to generate white noise signal from a given PSD?
One can just create the desired waveform that has psd = S0 without resorting to S/N. The example below has a crazy large unphys...
How to generate white noise signal from a given PSD?
One can just create the desired waveform that has psd = S0 without resorting to S/N. The example below has a crazy large unphys...
5개월 전 | 0
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How can I replace the upper off diagonal(super diagonal) and lower off diagonal(sub diagonal) of a matrix?
Hello Olawale m = rand(5,5) m1 = diag(m,1) % original upper diagonal a = [2 3 4 5]' % new upper diagonal elements mn...
How can I replace the upper off diagonal(super diagonal) and lower off diagonal(sub diagonal) of a matrix?
Hello Olawale m = rand(5,5) m1 = diag(m,1) % original upper diagonal a = [2 3 4 5]' % new upper diagonal elements mn...
5개월 전 | 1
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double and triple integral for a complex function. I coded but did not get any output
Hi Orpita, Here is a way to at least reduce the dimension of the integral from 5d to 3d. First of all, the quantity (x+1/2) se...
double and triple integral for a complex function. I coded but did not get any output
Hi Orpita, Here is a way to at least reduce the dimension of the integral from 5d to 3d. First of all, the quantity (x+1/2) se...
5개월 전 | 0
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Logarithmic trendline equation of data
Hello Cem, As has been mentioned you can use the curve fitting toolbox for this job, but if you don't have it you can try a sim...
Logarithmic trendline equation of data
Hello Cem, As has been mentioned you can use the curve fitting toolbox for this job, but if you don't have it you can try a sim...
5개월 전 | 0
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How change two columns with 5 rows to a single row?
Hi Bajdar, xy = [x; y]; z = xy(:)' i.e. concatenate x and y vertically, read that matrix out columnwise, then take the transp...
How change two columns with 5 rows to a single row?
Hi Bajdar, xy = [x; y]; z = xy(:)' i.e. concatenate x and y vertically, read that matrix out columnwise, then take the transp...
5개월 전 | 0
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답변 있음
Hi, I am applying findpeaks function to find the peaks of an oscilloscope signal but in the peak plot graph it is automatically changing the x-label with a large difference.
Hi Rikita, if you use findpeaks(y,x) where x is the x axis (linear or log scale) whose min and max match the oscilloscope trace ...
Hi, I am applying findpeaks function to find the peaks of an oscilloscope signal but in the peak plot graph it is automatically changing the x-label with a large difference.
Hi Rikita, if you use findpeaks(y,x) where x is the x axis (linear or log scale) whose min and max match the oscilloscope trace ...
6개월 전 | 0
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Why such a fuss with ndgrid and meshgrid issues?
Hi Kristoffer, I totally agree that Mathworks should use nonsquare examples in the documentation for meshgrid, ndgrid, surf etc...
Why such a fuss with ndgrid and meshgrid issues?
Hi Kristoffer, I totally agree that Mathworks should use nonsquare examples in the documentation for meshgrid, ndgrid, surf etc...
6개월 전 | 1
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How do I find the phase for a periodic cos wave using fft?
Hi Noam, here is a version using time and frequency in the usual manner. A couple of ponts here. If you construct a grid as y...
How do I find the phase for a periodic cos wave using fft?
Hi Noam, here is a version using time and frequency in the usual manner. A couple of ponts here. If you construct a grid as y...
6개월 전 | 0
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how to write the right code to measure the elapsed time of this method d1 = diag(1./diag(A))
Hi Amna, A common way to do this is with tic and toc. So: a = rand(1e4,1e4); tic b = diag(1./diag(a)); toc Elapsed time...
how to write the right code to measure the elapsed time of this method d1 = diag(1./diag(A))
Hi Amna, A common way to do this is with tic and toc. So: a = rand(1e4,1e4); tic b = diag(1./diag(a)); toc Elapsed time...
6개월 전 | 0
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using polyval with one of the polynomials of a spline obtained with the unmkpp command, the results do not overlap! Why?
Hello TH,. spline polynomials are local to the secgment in question starting from x = 0, so if an interval is, for example 3 to...
using polyval with one of the polynomials of a spline obtained with the unmkpp command, the results do not overlap! Why?
Hello TH,. spline polynomials are local to the secgment in question starting from x = 0, so if an interval is, for example 3 to...
6개월 전 | 1
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Multiplication of submatrices of a matrix
Hi Laura, if I interpret this correctly, you have n rows (I'll use small letters mostly) of the form Anew = [c c*b1 c c*b2 ...
Multiplication of submatrices of a matrix
Hi Laura, if I interpret this correctly, you have n rows (I'll use small letters mostly) of the form Anew = [c c*b1 c c*b2 ...
7개월 전 | 0
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matrix inverse results different between r2023b and 2021b
Hi QL. you called both the inverse matrices '2021b' so I called the first one F and the second one S (and the orginal matrix is...
matrix inverse results different between r2023b and 2021b
Hi QL. you called both the inverse matrices '2021b' so I called the first one F and the second one S (and the orginal matrix is...
7개월 전 | 0
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