Answered
Accidental deletion of project, how to contact file exchange admin
Why did you do that? Silly question, I know. ;-) Yes, it should be undoable. I'll contact the FEX admin and ask them to resolve...

1 year ago | 0

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Answered
Complex multiplication giving incorrect result
Yet another person who does not understand the realities of double precision arithmetic. Note that the imaginary part is roughl...

1 year ago | 2

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What is the best kind of MATLAB function to teach beginners?
I think I agree with @Stephen23, in that teaching symbolics first can cause issues. We see many new users who think everything s...

1 year ago | 1

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Answered
Different results of the same caculation by loop code and by array code
As is almost always the case, when we see this complaint, it is because you do not understand how arithmetic works in terms of d...

1 year ago | 0

Answered
我买了学生版
Are you sure you have the student edition, and not the 30-day free trial? It would appear you have gotten the trial version, by ...

1 year ago | 0

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MINLP problem in MATLAB with both integer constraints and nonlinear equality constraints
NOPE. Were I writing that code, hoping to solve a problem with integer variables, and general nonlinear equality constraints, et...

1 year ago | 1

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How to stabilize the edge effects in a cubic B-spline?
You don't show any data, so there is little we can actually do in a constructive way. But you don't have a great deal of control...

1 year ago | 0

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Answered
What is the origin of "Weissinger Implicit ODE"
I usually laugh at the results of the AI tools available. Half the time they are blowing smoke, since they don't really understa...

1 year ago | 0

Answered
my code does not have an answer
The failure of both vpasolve and fsolve suggests it is lkely no solutions exist at all for your problem. But merely the failure ...

1 year ago | 0

Answered
Improved Euler's method compared to 4th order Runge - Kutta's method
Is it as good? COMPARE IT TO THE ANALYTICAL SOLUTION! We have gone through exactly this before. A big problem however, is you a...

1 year ago | 0

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Answered
Clarification on Calculations for $v_{1,z} $ in "A Method for Verifying the Generalized Riemann Hypothesis"
I think, from almost line 1 of what you did, you don't understand double precision arithmetic, and that will cause everything yo...

1 year ago | 0

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Is the methodology used in "sdRemoveImpossibles" a heuristic or is it derived from an academic publication?
Note that just because something is found in a paper, does not make it even necessarily good mathematics. The lack of any requir...

1 year ago | 0

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Infinite while loop for Euler's method in order to solve ode
I think you misunderstand what is happening. Your ODE is y' = y - y^2/2 ymax is found when y' = 0, and so you find that y...

1 year ago | 0

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Answered
generate random numbers among each non zero column elements
This is a 7 year old question, so there is probably no real utility in my posting an answer. But it is an interesting question t...

1 year ago | 0

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Surface triangulation of 3D points cloud
A common solution is to use a CRUST code. In fact, there is a version of CRUST to be found on the File Exchange, here: https://...

1 year ago | 0

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Identify two linear trends from the data
The amount of noise in your data makes it almost impossible to estimate the two trends in any intelligent way, even assuming the...

1 year ago | 0

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Answered
How can I make the following heatmap smoother while preserving the contours outlined by the green line?
I don't think interpolating your data will fix the problem, as your data is seriously bumpy. load DataMe.mat surf(TPP) view(...

1 year ago | 0

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Cannot Understand a Command
I would guess what they did was to ask you to write a matrix by something like the following description: M(a,b) = a + b w...

1 year ago | 0

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Solving non linear system with fsolve
Whenever you have a problem with hugely varying constants in it like this, it makes sense to consider if you should transform th...

1 year ago | 0

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How do I find the equation of points on a spline curve?
This is a question that gets aslked many many times about splines. And, well, you can't easily get a simple equation, as there i...

1 year ago | 0

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Too many input arguments error in objective cost function using fminsearchbnd
Did it even work using fmincon? I can't test that out, since we lack your data. And lacking your data, I can't test fminsearchbn...

1 year ago | 1

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Answered
How to map voltage to battery percent?
This is just a simple linear interpolation. Think about it! Suppose you subtract 45 from the voltage. When V was zero, you now ...

1 year ago | 0

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Answered
Constraint set to be a real number
First, constraints like: AV_constraint_1 = isreal(A_v); are not differentiable. Sorry. They can't be used in fmincon. Well, y...

1 year ago | 0

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Answered
Numerical integration (Trapezoid, Simpson, Gauss)
"shouldn't Gauss' 3 points method give the best value for the integral ?" Why? In fact, no. There is no reason for that to be t...

1 year ago | 0

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Why does MatLab give non integer values for whole numbers?
It is not even remotely ridiculous. Are you seriously claiming that the vector [0.7071;0.7071] is NOT a null vector? Any mult...

1 year ago | 1

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Answered
Does anyone know how to get solve to work with one of the variables being a range
Solve does not directly allow you to define a variable as being in a range, but assume will help you out, as I show below. Anywa...

1 year ago | 0

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Algorithm which finds lower bound of the epigraph of a discrete 2D curve which is not a function (i.e. fails vertical line test)
Is there an algorithm that solves it in some slick way? Not that I know of. How would I solve it? Treat this as a way to find ...

1 year ago | 1

Answered
Simplify in GF(2)
In the help docs for simplify, we see: "S = simplify(expr) performs algebraic simplification of expr." The key word there is A...

1 year ago | 0

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Answered
Hello I am solving a lp problem and linprog shows the wrong answer. If I solve it with fmincon, I get the answer.
H= @(i,j) exp(-abs(i-j)); % anonymous function m= 4; noise_pow= 1e-9; g= [15; 12; 9; 6]; A= [-H(1,1), g(1)*H(2,1), g(1)*H(3,1...

1 year ago | 1

Answered
Cumtrapz integration drift with time
This is expected behavior. And reducing the time step WILL reduce the problem. And it IS something purely mathematical, yes, you...

1 year ago | 0

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