Answered
simplify function does not work properly
Consider a simpler case syms x y term1 = x - 1; term2 = y - 2; eq = term1*term2 assume(term1*term2 == 0) simplify(eq) sim...

4 years ago | 0

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Answered
Closed form not the same as the discrete form
Hi Tworit, I'm not quite following how the code is trying to implement equation 41 from the linked page. Here is one way to cre...

4 years ago | 0

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Answered
Removing all elements from a struct field
Does rmfield meet the need? % create a struct for example for ii=1:13 aap.acq_details.sessions(ii).name = ii; end aap.acq_d...

4 years ago | 0

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Answered
Graphs using ode45 do not look like they should. Why is time vector not a linear set?
Hi Josh, Maybe the plots are deceptive. Running the code exactly as given, except for the plotting, shows that v is the derivat...

4 years ago | 0

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Answered
FT and Amplitude Phase plot in matlab
The code as shown has at least two issues. When using symbolic math, need to declare variables appropriately syms t w real Bec...

4 years ago | 1

Answered
Add Fields to an existing Structure
S.Level0=0; f = {'SubLevel0','SubLevel1','SubLevel2','Text'}; cvar = '1234'; S = setfield(S,'Level1',f{:},cvar); S.Level0 S...

4 years ago | 3

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Answered
please help to fix my code for 4th order Runge Kutta method for second order ODE.
Hi Siti Nafisah Bekti Lelana, Why do you think it's the wrong answer? I didn't check the equations, but the code seems to yield...

4 years ago | 0

Answered
calculate the Γ matrix in MATLAB from Φ Matrix - State space equation
Let's see what we have so far: A = [0 1; -1 -1]; b = [0;1]; I = eye(2); syms s; LaplaceTransitionMatrix = (s*I-A)^-1 phi =...

4 years ago | 2

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Answered
Cumulative sum in Simulink
The Discrete-Time Integrator block can be configured as an accumulator.

4 years ago | 1

Answered
How do I construct the dft response of hanning window
Hi Sahil, The code doesn't show the values of N and T used, so I'll make up my own. N = 64; % T = 1; Changed the next line s...

4 years ago | 0

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Question

Does surf() Behave as Expected with ndgrid() Inputs?
Define a function clear f = @(x,y) x; Case 1: square mesh, meshgrid, vector inputs to surf x = 0:5; y = 100:105; [Xmesh,Ym...

4 years ago | 1 answer | 0

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answer

Answered
Calculate convolution of two given continuous signals in matlab
Closed form solution using symbolic math syms t tau real f1(t) = rectangularPulse(-5,5,t); f2(t) = exp(-t)*heaviside(t); y1(...

4 years ago | 1

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Answered
Why does MATLAB (Symbolic Math Toolbox) not integrate this simple function.
syms x a real I = int(simplify((1-x^2/a^2)^(3/2)),x,-a,a)

4 years ago | 0

Answered
Behavior of isPassive and hinfnorm.
Hi Siva, I'm not able to load the .mat file, so can't really look at the problem. load('https://www.mathworks.com/matlabcentra...

4 years ago | 1

Answered
Question on use of fft and using positive frequency values only
Is this just an indexing question? If I understand the code snippet correctly, the frequency vector starts at 0, and incremente...

4 years ago | 0

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Answered
How do I solve a symbolic system for a certain vector?
Hi Vitor, To make sure I understand the question, it assumes that a rigid body can have a constant, non-zero angular velocity v...

4 years ago | 1

Answered
Adding a delay in state space form
The command sys=ss(A,B,C,D,'InputDelay',theta,'OutputDelay',0); puts a delay on the input signal, i.e., at the output of the a...

4 years ago | 0

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Answered
DFT amplitude differs from CFT amplitude
Hi An, A couple of issues with the code, addressed below. T_ech = 5E-5; y = [0 0 0 0 0 1 1 1 1 1 1 1 1 1 0 0 0 0]; t = [T_ec...

4 years ago | 0

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Answered
Step response and Impulse response of IIR filter
Hi Alex, It would be helpful to know the value of temp. Absent that, it seem like [hstep,tstep] = stepz(sos); hstep = hstep*...

4 years ago | 0

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Answered
Incorrect Integrator Behaviour Simulink
It looks like the input sine wave is sin(2*pi/2*t) = sin(pi*t) The output of the integrator should be -1/pi*cos(pi*t) + C B...

4 years ago | 1

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Answered
Change the size of a log in simulink
Double click the ToWorkspace block and increase the Decimation parameter. If you really need all of the data, maybe something m...

4 years ago | 0

Answered
Designing an Observer - Control System
I don't think you're going wrong anywhere (though you might want use size(Aa,1) instead of length(Ca) in a few places). I think ...

4 years ago | 0

Answered
Plot a 2D Gaussian prior
Something like this? mu = [1 1]; Sigma = [1 .7*1*sqrt(2); .7*1*sqrt(2) 2]; [X,Y] = meshgrid(-2:.1:4); p = mvnpdf([X(:) Y(:)]...

4 years ago | 0

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Question

Is exp() a Documented Function in the Symbolic Math Toolbox?
I can't find it.

4 years ago | 3 answers | 0

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answers

Answered
adding a communication delay in simulink
Try using the LTI System block.

4 years ago | 0

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Answered
Calculate convolution of two given continuous signals in matlab
Assuming a closed form solution is desired this problem can be solved with the Symbolic Math Toolbox syms rectangularPulse in...

4 years ago | 2

Answered
Why do the eul2quat and quaternion functions differ on the calculated results?
Hi cui, I think that both eul2quat and quaternion('frame') are using, right-handed, intrinsic rotations and the sequence of rot...

4 years ago | 1

Answered
roots(x) vs root= interp1(y,x,0)
The query points in x are spaced too far apart for the linear interpolation used by interp1 to be accurate relative to the actua...

4 years ago | 0

Answered
Fourier transform of a rectangular pulse
Hi Luke, Your original code was o.k. except for plotting against t. It is typically plotted against an array of frequencies. Al...

4 years ago | 1

Answered
Calculation of Phase margin
Hi T, it's a tricky problem becase of the shape of the gain curve around the phase cross over frequency. w=1.4910; k=sqrt((w^4...

4 years ago | 0

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