Answered
How to expand symbolic exponential numerator to reduce fraction
syms Y_t A_t K_t alpha L_t k_t w_t y_t Y_t = A_t*K_t^alpha*L_t^(1-alpha) lil_y = y_t == Y_t/L_t labor_eqn = L_t == solve(li...

3 years ago | 0

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Answered
Bessel filter analog to digital
Hi Maurizio, freqs returns the frequency vector, wb, in units of rad/sec. freqz, as used below, returns the frequency vector, ...

3 years ago | 1

Answered
Conditionally executed functions in Simulink
A Triggered Subsystem may fit the bill. More generally, check Conditionally Executed Subsystems for more discussion.

3 years ago | 0

Answered
how to preferentially compute vector products rather than matrix products
"Is there any way to change this setting without bracket?" No. From the doc page for Operator Precedence: "Within each preceden...

3 years ago | 0

Answered
inverse Laplace transform in simulink
The Matlab Function block does not support any symbolic operations, as far as I know. I think the best you can do is structure t...

3 years ago | 0

Answered
Functions specgram and spectrogram - what does the spectogram' 3rd dimension mean and what unit it has?
Hi Peter, Until I read this question, I had never really thought about the outputs of spectrogram in an absolute sense. I only ...

3 years ago | 1

Answered
One of the systems I want to control includes disturbances in the input matrix. How can I convert this state space equation into a transfer function?
Combine u and d into a single input vector. Then the "B" matrix is composed of the Bbar and Ebar matrices concatenated together ...

3 years ago | 1

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Answered
Hello: i want to give a step input to my simulink function which starts at 1 second and ends at 1.1 seconds and having an amplitude of 0.1. Step block not working
Try using the Waveform Generator block with Waveform Definition parameter set to pulse with appropriate parameters. However, the...

3 years ago | 0

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Answered
why lsim return empty states?
According to the lsim doc page, the output x is returned when the input sys is a state-space model. The doc page further distin...

3 years ago | 0

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Answered
create a new array with group sum
Check out splitapply

3 years ago | 0

Answered
Incorrect number or types of inputs or outputs for function 'step'
Hi Archit, It would be much easier to help if you copy/paste the actual code into the Question rather than a large screen captu...

3 years ago | 0

Answered
ss2tf taking too long
Which version of ss2tf are you using? The one that ships with Matlab which -all ss2tf doesn't support sym inputs syms a b c d...

3 years ago | 0

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Answered
logging data from Simulink to workspace
Hi Asmaa, Because the signals are already in the simulation, why would there be a need to send them from Simulink to Matlab onl...

3 years ago | 0

Answered
Assistance with Transfer Function Output
The second input to lsim, called 'input' in the code, has to be a vector (becuase Hd is single input) of numerical values. So yo...

3 years ago | 0

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Answered
How to extract coefficients of custom variables in symbolic expression in MATLAB?
syms psi phi theta i_B j_B k_B psi_dot phi_dot theta_dot omega_B = (phi_dot - psi_dot*sin(theta))*i_B + (theta_dot*cos(phi) + p...

3 years ago | 0

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Answered
Discrepancy in PI Controller Outputs for voltage control and current control for droop control strategy in MATLAB
With regard to this part of the code: % //PI controller for Vd error_vd(n)=((sqrt(2))*Vd_ref(n))-(V1d(n-1)); ...

3 years ago | 0

Answered
We have table，Why we use timetable？
It looks like timetables offer additional functionality helpful for dealing with time histories of data: Timetables

3 years ago | 1

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Answered
creating cell array using find command
Hi Amit, Just need to prepend the index vector to keep the first column. rng(100) analysisdataacd3 = num2cell(randi(3000, 10,...

3 years ago | 0

Answered
Receiving an error when using interp2 to interpolate longitude and latitude (Error using griddedInterpolant Grid arrays must have NDGRID structure.).
lon = xlsread('lon.xlsx') ; lat = xlsread('lat.xlsx') ; elevation = xlsread('elevation.xlsx') ; interp2 requires matrix input...

3 years ago | 0

Answered
PID Controller in Simulink question
Set the 'Source' parameter to 'external' as in doc for PID block. The you can calculate the gains external to the block as funct...

3 years ago | 1

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Answered
Problem in filtering my desired frequency
Hi Abdullah, A couple of issues to address in the anlaysis. I think you started by trying to define an ideal filter in the fre...

3 years ago | 0

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Answered
Problems in dynamic symsum variables in solving a system of equation
Hi Tsz Tsun, Why not just use regular sum instead of symsum when the goal is to just take the sum of a finite number of terms? ...

3 years ago | 2

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Answered
Problem in plotting the convolution
Hi Abdullah, Although not stated explicitly in the Question, I'm going to assume that a) the objective is compute the convolut...

3 years ago | 0

Answered
how to interpolate stepfunctionresponse
Hi Hassen, I don't undertstand how the matrix i fits into the problem, and I assume that one column of the Matrix is a time vec...

3 years ago | 0

Question

Is there a way to Rewrite a Symbolic Expression in Terms of nthroot?
Suppose I have a symbolic expression syms x real g = x^(1/3) - 1 I'd like to evaluate g for negative values of x, either symb...

3 years ago | 1 answer | 0

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answer

Answered
get x knowing f(x)
finverse works well in this case. syms f(x) y f(x) = exp(x); g(y) = subs(finverse(f),x,y) g(23)

3 years ago | 0

Answered
acker(): "Error using sym/poly". Why?
Hi John, A = [0 1; -4e5 -400]; B = [0; 4e5]; C = [1 0]; Aaug = [A, zeros(2,1); -C, 0]; Baug = [B; 0]; H = 1.0e+12 *...

3 years ago | 1

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Question

What are Your Thoughts on TMW Documentation Linking to the File Exchange
Kind of similar to this Question, I noticed that the Tips section of integral3 cites this File Exchange submission as an option ...

3 years ago | 2 answers | 0

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answers

Answered
Why am I getting different frequency responses for the same filter using bode() and fvtool()?
Hi Rinitha, Here is the design of the low pass filter fs = 500; % Sampling frequency Ts = 1/fs; fc = 100; % Cutoff frequency...

3 years ago | 2

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Answered
Reference Frame for Forces Going into 6DOF (Euler Angles)
According to 6DOF (Euler Angles), the force inputs are the components of the net force resolved in Body Coordinates. If the "Z d...

3 years ago | 0

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