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how to create a polynomial interpolation of two variables
Sorry, but this is a common mistake made by people. You really have only ONE variable there, since x and y are linearly related...

3 years ago | 0

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Projection problem as a for loop
Your main problem is that the vector Ca is not composed of double precision numbers. That causes the code to fial, because the f...

3 years ago | 0

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how to work with a variable as a function of time?
Why MATLAB shows a partial derivative there, and not an ordinary derivative? syms theta(t) dTdt = diff(theta,t) Technically, ...

3 years ago | 0

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How to Plot a 4D polyhedron
Do you have a 4-dimensional hypermonitor? Perhaps you use a holodeck to do your plots? Oh, wait, you cannot get things like that...

3 years ago | 0

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cos block error (simulink)
Welcome to the wonderful, wacky world of floating point arithmetic. Is the number format long g pi/2 EXACTLY pi/2? cos(pi/...

3 years ago | 0

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How can I assign to a variable an interval of numbers.
You cannot just tell MATLAB that a normal variable is any value in some interval. Effectively, this requires interval arithmetic...

3 years ago | 1

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Faster alternative to polyxpoly
Nothing is ever as fast as we want it to be. polyxpoly (part of the mapping toolbox) does a lot of work. And it needs to check f...

3 years ago | 0

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How to find symmetry axis of set of 2D-points?
Interesting question. If there is a true exact line, one that forms a perfect line of symmetry, then the SVD should identify it....

3 years ago | 1

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Got this ''Empty sym: 0-by-1''
I'll suggest you did things in the wrong order. syms x syms q % leave q as an unknown parameter for the moment. w = 2; eqn =...

3 years ago | 1

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How to restore built-in functions in toolbox to the original version
NEVER EDIT MATHWORKS SUPPLIED FUNCTIONS. A rule I use for my own code is, if you change it, you own it. Any future problems are...

3 years ago | 0

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How to represent [airfoil] coordinates as a polynomial
xy = [0 0 0.00369000000000000 0.0134500000000000 0.0170200000000000 0.0280700000000000 0.0336900000000000 0.03900...

3 years ago | 1

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Answered
How to find the vector b if we know the RMSE?
There are infinitely many possible vectors b, for any given RMSE. And worse, they can have infinitely many possible shapes. This...

3 years ago | 0

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A simultaneous linear equation with coefficients as variables
I assume you mean simultaneous linear equations where the coefficients are parameters that are assumed to be fixed, and not esti...

3 years ago | 0

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Create Matrix of coefficients from nonlinear function
I'm sorry, but you are most certainly incorrect. A system of 4 equations like that would have 4 unknowns. In what you were sho...

3 years ago | 0

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Create a boundary using points
This is often achieved using the CRUST algorithm. A quick search just found several links that have MATLAB code for CRUST. A qu...

3 years ago | 1

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is Matlab code a lot faster than Excel formulas?
A problem is that you have said it is a lot of conditional expressions. The thing is, MATLAB will be fast, IF you can use the ca...

3 years ago | 1

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How to optimize when the objective can be negatively influenced
This is just an optimization problem. Use any appropriate optimization solver. Note that the optimizers are typically minimizers...

3 years ago | 0

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Pseudorandom sequence with costrains with frequent and infrequent elements
Simple. Start with the requirement. You have a sequence where you want 150 elements, 30% of them to be the infrequent case. Bu...

3 years ago | 0

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maximization nonlinear problem and local maximum solution
Whenever I try to squeeze blood from a rock, all I ever do is get my hands all bloody with my own blood from my own fingers. The...

3 years ago | 0

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How can we generate all n by n matrices with entries {0,1,2,...,m-1} for any natural numbers m and n?
So, for the simpler case of how to solve for ALL 2x2 matrices, containing the integers 0:6, just work in base 7. M = reshape(de...

3 years ago | 0

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Is using the Trapz function equivalent to using the Mean function in MATLAB ?
NO. It is not the same thing. Can it, under some circumstances be approximately the same? Well, with multiple caveats, yes. Some...

3 years ago | 0

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How can we generate all n by n matrices with entries {0,1,2,...,m-1} for any natural numbers m and n?
Assuming you mean with replacement, then yes, the total number of those matrices is m^(n^2). For m and n even reasonably large, ...

3 years ago | 0

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How to solve a semi-definite programming with l1-norm objective?
This is an optimization problem, but I would argue it has been posed poorly. If you want to constrain the matrix A to be positiv...

3 years ago | 1

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parameter Heligman pollard
Given only 17 data points, estimation of 8 highly nonlinear parameters will be almost impossible. Sorry. x1=[0;1;5;10;15;20;25;...

3 years ago | 0

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exitflag in fminsearch
It is NEVER possible for fminsearch to return a decimal value for the exit flag. That presumes there was no accidental modificat...

3 years ago | 0

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bilinear curvefit
This is essentially just a linear spline, so a pair of piecewise linear segments, continuous at the join point. The problem is,...

3 years ago | 0

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Sorting of trigonometric functions
The simplest way to achieve what you want is to compute the sin, and then do the sort. Anything else you could do would be more ...

3 years ago | 0

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Answered
finding values of implicit function of 3d
So you have the relation: a=0; b=10; T=3; e = exp(1); ux = 90; v = 70; syms u t x b^u*(ux/e*u)^(v*t/2) == b^(x/2) (Please...

3 years ago | 1

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How to write an inequality constraint to solve NLP problem by fmincon
They are NOT TWO constraints. They are FOUR constraints. Just because you want to be efficient in how you write them in terms of...

3 years ago | 0

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Answered
How do I plot from excel different columns file?
You were ALMOST there. Literally, almost. You need the x axis variable. Here is your array: numbers = [1 6 7 4 3 3 4 7;2...

3 years ago | 0

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