Question

What New Functions or Features in R2023B are of Interest?
I was reading this question where Steve Lord suggested using a function expmv that is new in R2023B. I went over to the Matlab R...

2 years ago | 2 answers | 0

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What do the states in a series connection of a plant with time delay (approximated by pade approximation) represent ?
Hi Janki, "What do the first 2 states here represent? " Each state is the state variable of the state space realization of the...

2 years ago | 0

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Best practice: should a function return a row vector or a column vector
I just ran into a case where I had to make sure the output vector from a function had to have the same dimensions as a vector in...

2 years ago | 2

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I want to perform inverse Laplace transform but my code does not seem to work
Hi Carlos, ilaplace assumes that all signals are causal, which wouldn't be true in this case if a < 0. Add the appropriate ass...

2 years ago | 1

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Bode plot of a 157 order transfer function
Hi Dongxu Guo, That's quite a filter! Using a tf for a for such a high order filter is not likely to work due to large roundin...

2 years ago | 0

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The normal "state space" and "discrete state-space" block in Simulink have different results
Hi Christian, If the simulation step size is fixed at 1e-6, then the inherited Sample Time of the Discrete State Space block is...

2 years ago | 0

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Proper way to call designfilt for filtfilt
The example above is a low pass, linear phase FIR filter. Maybe a simple delay as is implemented in lowpass is acceptable? Cuto...

2 years ago | 1

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MATLAB telling me there are no real values to my step response when there are
Hi Sophie, It looks like that message will come up when calling step with a tf input with complex coefficients h = tf(1,[1+1i,...

2 years ago | 0

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How to Obtain State Space Model from Bode Plot Data
Hi Muhammad, Here is the first part of the code: T2 = readtable('E7i_CSV.csv'); ...

2 years ago | 1

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Getting an equation from a signal transfer function
Hi Sifiso, Here is an example that might be helpful. Generate an input signal inputAudio = sweeptone(6,0.1); Fs = 44.1e3; N...

2 years ago | 0

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How to avoid defining variable value with simulink.
No, this can't be done in Simulink, nor in the Control System Toolbox. With G1(s), G2(s), and H(s) define as symfun objects, you...

2 years ago | 0

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Why I am not getting sample time in the discrete transfer function block.
Hi Gokula, The Discrete Transfer Fcn block is one of the Blocks for Which [Setting] Sample Time Is Not Recommended. Instead, Si...

2 years ago | 0

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The problem is to obtain the eigen einergies of the Schrodinger equation for an array of l = 0:1: 5 and del = linspace(0,1,N)
hbar = 1; mu = 1;e = 1;De = 1;re = 1;alp = 0.01;N = 100; l = 0; del = 0; L = l.*(l+1); r = linspace(1,1.2,N);dr = r(2)-r(1); ...

2 years ago | 0

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How do we choose matrices in state feedback control?
Hi Luc, For lqr, the B matrix multiplies the control input. As I don't know what the variables mean in your problem, I can only...

2 years ago | 1

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Why am I getting this error "Conversion to logical from sym is not possible." in line 18?
syms x syms y %f(x,y) = input("Enter the function of f(x,y): "); f(x,y) = x^4 + y^4 -2*x^2 + 4*x*y - 2*y^2; df_dx = diff(f(x...

2 years ago | 0

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Reducing symbolic expressions with assumptions, but NOT simplify?
Hi Aroni, Consider the simple expression syms x f(x) = sin(x)/sqrt(1-cos(x)^2) Simplify simplify(f) If we assume that x is...

2 years ago | 0

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I got error with "error using plot, vectors must be the same length"
Hi Tran, Next time, please copy/paste your code into the Question, which makes it much easier for people to help. Original cod...

2 years ago | 0

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Jumps in signal connections - simulink
Hi Tobias, From the Matlab window: Click Preferences in the Environment ribbon. Select Simulink in the preferences window. C...

2 years ago | 0

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I need to put this block diagram in MATLAB (not in Simulink) and I do not know how to do it
Hi Carlos, Recheck the definiton of s2. Once you have that taken care of, I suggest you proceed with connect.

2 years ago | 0

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I don't know how to introduce the block (s+6) in simulink
Hi Carlos, One option would be to use block diagram manipulation. For example (there is at least one other approach): a) chang...

2 years ago | 0

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Valid Shape FFT Deconvolution
Hi Benjamin, Here's an approach for the 'valid' convolution. Problem parameters: x = 1:7; nx = numel(x); h = 1:3; nh = numel...

2 years ago | 0

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Simulink - Saving Base Workspace Variables
One option is to use the Model Workspace: "Each model is provided with its own workspace for storing variable values."

2 years ago | 1

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Matrices size difference within for loop and unable to perform assignment of elements
Hi mcp0228, The loop variable iNepochs will be a scalar value, hence the LHS of the assignment is a column vector. for iN...

2 years ago | 0

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Why is Symbolic Math Toolbox Giving Decimal Answers?
Check your sympref The defaults are sympref Resulting in [sym(pi) sym(sqrt(3))] But, if you change this pref sympref('Floa...

2 years ago | 0

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Change content of Simulink Matlab Function block through console
Use MATLABFunctionConfiguration and modify the FunctionScript property.

2 years ago | 0

Question

Can the Symbolic Math Toolbox Be Used to Prove Matrix Identities?
With the following defintions syms s A = symmatrix('A',3); B = symmatrix('B',[3 1]); C = symmatrix('C',[1 3]); L = symmatri...

2 years ago | 1 answer | 0

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getLoopTransfer is giving the same open loop transfer functions for two different systems
Hi Janki, I'd have to go through the math on the two calls to getLoopTransfer to determine if that result makes sense. Offhand,...

2 years ago | 1

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using hasSymType(expression, 'constants') returns true when no constants
Hi Andrew, Both of those examples seem to be in accordance with doc hasSymType and children, except that children returns a cel...

2 years ago | 0

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Can't get symbolic numbers.
Hi Austin, Seems to work here as you expect. sym(1/5) sym(1/5,'r') But the preceeding results are based on the default sympr...

2 years ago | 1

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FFT is shifting my artificial signal?
Hi Zach, a) create the X vector with spacing based on the sampling frequency, Fs b) create the wave vector with sinusoids comp...

2 years ago | 0

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