Answered
insAccelerometer Documentation h(x)
My take on this ... The equations in the code make sense assuming (1) the accelNav vector, which I assume (2) is a filter state...

5 months ago | 1

Answered
Error with Calling "dcmecef2ned" in Simulink
Hi Richard, In which version did it used to work? I'm assuming you're calling dcmecef2ned from inside a MatlabFunction block? ...

5 months ago | 0

Answered
Having trouble solving an equation
syms x eqn = sqrt(((((26892/(x)^3)+(254.7/(x^2)))/2)^2)+(6111.5/((x)^3))^2) == 19000; expand(eqn) solve is telling it can't f...

5 months ago | 0

| accepted

Question

Does Symbolic Math Toolbox Formally Support Function Composition?
The doc page Create Symbolic Functions states "The Symbolic Math Toolbox™ currently does not support composite symbolic function...

5 months ago | 1 answer | 0

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answer

Answered
Wrap part of a shape with a surface
Hi Robert, Perhaps something like this that draws a pathc between each height line? Salt to taste on the patch command. Is th...

5 months ago | 0

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Answered
Weird behavior with Three-axis Inertial Measurement Unit
"Is the purpose of the IMU to simulate a real-life IMU, or something else?" The purpose of that model is to simulate a notional...

5 months ago | 0

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Answered
Newtonian Mechanics vector solution needed to find the range of forces (P) that satisfy Fnetx = 0
Here is an algebraic solution; I suspect one could do the whole thing symbolically and then sub the numbers at the end. Note th...

5 months ago | 0

Answered
Bode plot with right half plane zero
Hi @Anindya, The bodeplot function offers options on controlling the appearance of the plot, including to force the phase betwe...

6 months ago | 1

Question

Why is Answers Now Showing "Ran in" Links?
AFAICT, the "ran in" link is just a link to the same question.

6 months ago | 1 answer | 0

1

answer

Question

Why Doesn't a Symbolic Matrix Equation Simplify Until After Applying subs() ?
Following code is to derive an expression for the derivative of the magnitude of a vector function of time. clearvars syms t r...

6 months ago | 1 answer | 0

1

answer

Answered
Obtaining the differential equations from graphical representation of the problem
One can implement the equations of motion in Simulink and then use linearize to get the differential equation, but that requires...

6 months ago | 0

Question

Is Assignment from symmatrix/symfunmatrix Consistent with Assignment from sym/symfun ?
I've just started using symmatrix and symfunmatrix and noticed a behavior that I don't understand and seems to be inconsistent w...

6 months ago | 0 answers | 1

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answers

Question

How Does the 'All' Option Affect the Result of Symbolic simplify?
Start with a simple expression syms alpha beta real f = cos(beta)-cos(beta)*cos(alpha)^2 and try to simplify it: simplify(f)...

6 months ago | 1 answer | 0

1

answer

Answered
RC Circuit Simulation in Simulink Shows Incorrect Charging Time
Hi Xiaolong, Disclosure: I did not actually open your model. If you know the fastest system dynamics are on the order of 1e-6,...

7 months ago | 0

Discussion

It is Time for the Symbolic Math Toolbox to Include dot and cross Functions
Edit 15 Oct 2025: Removed incorrect code. Replaced symmatrix2sym and symfunmatrix2symfun with sym and symfun respectively (latte...

7 months ago | 0

Answered
Gibbs-like behaviour with lowpass on long signals
Hi qfn, I think that lowpass, et. al. will result in transients due the large, effective steps at the endpoints. I think this ...

7 months ago | 0

Answered
What frame of reference is the CG input to the IMU in Aerospace pack?
Hi Mats, According to IMU Location the CG input is to be provided in a coordinate frame that is fixed to the body. However, the...

7 months ago | 0

Answered
Indexing based on part of a string
column1 = [1;2;1;2;1]; column2 = ["2025-02 A";"A 2025-02";"B";"a 2025-02 a";"b 2025-02 b"]; T = table(column1,column2) T(T.col...

7 months ago | 1

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Answered
Run multiple Simulink model in parallel
Check out Run Multiple Simulations and links therefrom.

7 months ago | 2

Discussion

Will Disucssions Front End be Updated to be Consistent with Back End?
Apparently, the back end here is running 2025b, hovering over the Run button and the Executing In popup both show R2024a. ver m...

7 months ago | 0

Answered
ilaplace doesn't handle tanh()
Hi Marcel, I attempted to recreate the example with the information provided, but got a different result. syms s syms T posit...

7 months ago | 1

Answered
Control System Designer: Inconsistent Controller Output Step Response
I can recreate these result and uc/r certainly looks incorrect. After exporting the systems to the base workspace I get: >> tf(...

8 months ago | 0

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Answered
tf2sos input argument
Hi Nicolai, As far as I know, discrete time transfer functions in the Signal Processing Toolbox (SPT), whether b/a or sos form,...

8 months ago | 1

| accepted

Answered
iztrans not giving correct result?
syms z n The fact that the default value for heaviside(0) = 1/2 doesn't matter here, but should be kept in mid in general. x...

8 months ago | 0

Question

What Is the Behavior of Symbolic nchoosek With n < 0 ?
According to nchoosek:Algorithms "If k < 0 or n – k < 0, nchoosek(n,k) returns 0." syms n k f(n,k) = nchoosek(n,k) Using the...

8 months ago | 1 answer | 1

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answer

Answered
Analytic solution of quatric polynomial does not add up
Hi thejinn1314, simplify-ing the general solution with IgnoreAnalyticConstraints might be useful, though perhaps could cause so...

8 months ago | 0

| accepted

Question

Why Does Answers Run Code in 2025a But the Run Button, the "Executing In" Popup, and the "Ran In" Tag Still Show 2024b?
ver

8 months ago | 1 answer | 3

1

answer

Answered
Numerical precision issues when using tf('s')
I thin the general recommendation is that zpk is superior to tf, and that ss is superior to both. See Using the Right Model Repr...

8 months ago | 1

| accepted

Question

How Do Assignment and Deletion Work with an Empty Index on the Left Hand Side ?
I've always thought that indexing with an empty array on the LHS of an = is a no-op for the variable on the LHS (there could be ...

8 months ago | 1 answer | 0

1

answer

Question

Must a Function be in Scope Before Creating a Handle to It?
The doc page Create Function Handle states: "Keep the following in mind when creating handles to functions: Scope — The functi...

8 months ago | 1 answer | 1

1

answer