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...

19 jours il y a | 2 réponses | 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...

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...

21 jours il y a | 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...

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...

environ un mois il y a | 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...

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...

environ un mois il y a | 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...

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...

environ un mois il y a | 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...

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...

environ un mois il y a | 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...

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...

environ un mois il y a | 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,...

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,...

environ 2 mois il y a | 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'); ...

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'); ...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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); ...

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); ...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

Jumps in signal connections - simulink

Hi Tobias, From the Matlab window: Click Preferences in the Environment ribbon. Select Simulink in the preferences window. C...

environ 2 mois il y a | 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.

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.

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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."

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."

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 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...

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...

environ 2 mois il y a | 0

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Change content of Simulink Matlab Function block through console

Use MATLABFunctionConfiguration and modify the FunctionScript property.

Change content of Simulink Matlab Function block through console

Use MATLABFunctionConfiguration and modify the FunctionScript property.

environ 2 mois il y a | 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 mois il y a | 1 réponse | 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,...

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 mois il y a | 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...

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 mois il y a | 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...

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 mois il y a | 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...

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 mois il y a | 0

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