Answered
After taking the time derivative of a symbolic expression, how do you then differentiate that new expression with respect to another variable's time derivative?
Check out functionalDerivative syms y x(t) t y = sin(x); ydot = diff(y,t) syms Dx(t) ydot(t) = subs(ydot,diff(x,t),Dx(t)) ...

3 years ago | 0

Answered
Error using append and connect
Hi Abdul, The third input to connect, which is the connection matrix, is incorrect. It should have two rows. Check the doc page...

3 years ago | 0

Answered
How to set integrator to make it reset its state to zero when the output negative and the state is negative?
Hi 耘岑, If the queue length can never be negative, how is it that the model is resulting in a negative queue length? In any cas...

3 years ago | 0

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Answered
'InitFcn' Error in Simulink
Hi Sule, If running the simulation in the base workspace using the sim command or the run button, just load the .mat file into ...

3 years ago | 0

Answered
[Simulink] 'Discrete' state-space block with stable system diverging its output while 'continuous' one doesn't.
"The outcome is that, with exactly the same [A,B,C,D] matrices, ...." The A,B,C,D matrices mean different things in the State ...

3 years ago | 0

Answered
How can I use the output value from the first simulation reactor as init value of a second reactor simulation block in Simulink?
Hi Raúl, Change the 'Initial Condition Source' in the Integrator block to 'external'. The integrator will then have another in...

3 years ago | 1

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Answered
LQI(): integrator response not as expected
Before getting to the LQI part of this, I'm curious about the approach for making an LQR regulator into a tracking system. Here...

3 years ago | 2

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Answered
Error getting characteristics from Linear Analysis Tool and PID Controller
Hi Vasiliy, Change the analysis point at the output of the plant from 'Open-Loop Output' to 'Output Measurement'

3 years ago | 1

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Answered
Assumption Ignored Symbolic PDF
I'm not aware of a way to put an assumption like that on an integral. In this problem, it seems like the actual form of f(z) do...

3 years ago | 0

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Answered
Convolution between two PDFs using product of Laplace transforms in Symbolic Toolbox
E(x) and F(x) are not valid pdfs. syms x real E(x) = 2.*(1 - 0.01)*dirac(x) + rectangularPulse(0, 300, x).*0.01./300 F(x) = ...

3 years ago | 0

Question

Why Can't int Find a Simple Integral?
syms x real E(x) = 99/50*dirac(x) + rectangularPulse(0, 300, x)/30000 int on first term yields expected result int(99/50*dira...

3 years ago | 2 answers | 0

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answers

Answered
How does simulink use data stored in matlab as an array for each time iteration?
Hi M.I, 141 rows does not correspond to 15 sec with 0.1 step size. Perhaps it's just 14 seconds. Whether or not you need to us...

3 years ago | 0

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Answered
Surprising behavior in randsample
I don't see anything in the doc that says anything about the ordering. randsample is an .m file. The algorithm for without repla...

3 years ago | 1

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Answered
How make a high pass filter and give input to it simultaneously?
"How can i make a filter which can have a given cutoff frequency and also passes a custom made input (in the code)." Check out ...

3 years ago | 0

Answered
Rename integration variable in symbolic result
I don't know if I'd call this 'easily', but it gets the desired result (I believe). syms t m b y(t) y0 C x(t) % definitions of ...

3 years ago | 0

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Answered
Matlab - Bode plot of discrete and continuous Function
One problem is that the discretization of the product is not the product of the discretization. But with T_sample so small, tha...

3 years ago | 0

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Answered
I have a time domain signal.I want to calculate energy of my signal......
Suppose we have a continuous-time signal syms t f x(t) = exp(-abs(t/5))*sin(2*sym(pi)*2*t) This signal is noncausal and has i...

3 years ago | 0

Answered
Discrete Average on Simulink
If I understand the question correctly ..... Use a Discrete FIR Filter block to maintain a running average of 600 samples. Set ...

3 years ago | 0

Answered
InitFcn Error at Simulink
The model (likely) needs information stored in a file called bldcData.mat in order to execute, so the InitFcn callback tries to ...

3 years ago | 0

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How to plot the continuous convolution result
Hi YAMENG, Have you considered computing the convolution integrals directly? Note scaling to get them all to fit on the same ...

3 years ago | 0

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Answered
Determine the Length of One Oscillation
I think this problem is supposed to be attacked like this. Define H(z) syms z H(z) = (-3*z^2 + 4*z)/(8*z^3 - 14*z^2 + 8*z - 2...

3 years ago | 1

Question

Figure Control Buttons Out of Sync in Live Script
I'm running a live script. When I hover the mouse in the figure I the home, zoom out, zoom in, pan, and save buttons become vis...

3 years ago | 1 answer | 0

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Answered
Can I use a symbol as a variable?
Hi Prasenjit, Yes, you can do that syms m f = m^2 % expression that contains m as a symbol whos m % m is sym for m = 1...

3 years ago | 0

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How to plot frequency spectrum of a piecewise function in matlab?
Hi Daniel, Regarding this comment, the use of fftshift and the multiplication by dt both have to do with using the Discrete Fou...

3 years ago | 0

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Answered
I want to find the filtered signal and remove the noise from the discrete received signal from the radar and convirte it to continuos
c2d (Control System Toolbox) or c2d (System Identification Toolbox) requires the first input be a dynamic system model. As far a...

3 years ago | 1

Answered
I have an error when simulate a linear delay system with sliding mode control
Hi yousra, I'm not quite sure what the code is trying to do. However, the reason for the lsim error is pretty clear, and there'...

3 years ago | 0

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Answered
How can I use the matlab function like fcn block
Hi titor7, The reason for the error in the original model show in this comment is because Simulink didn't have enough informati...

3 years ago | 1

Answered
Can't susbsitute a variable that is defined
Do syms C1 before calling subs. syms y(t) a eqn = diff(y,t) == a*y; S = dsolve(eqn) syms C1 subs(S,C1,2)

3 years ago | 2

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Answered
Running simulink model with multiple values of a parameter, and then plotting multiple results on the same plot
Instead of, or in addtion to, the scope, send your data to a To Workspace block. Check out this doc page for an example of how ...

3 years ago | 0

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Answered
Why does the step response to my discrete system not match between MATLAB and Simulink?
The explanation for the Simulink resutls is that the coefficients entered in the Discrete Transfer Function block don't represen...

3 years ago | 0