Question

Should equationsToMatrix handle inequalities?
equationsToMatrix is a very nice tool. It works great to unpack an equality relation, like this: syms x y EQ = x + 2*y == 3 [...

3 years ago | 1 answer | 0

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polynomial curve fitting error
Is there a good reason why you called the script you wrote polyfit? Yes, I suppose you had a very good reason, because you wan...

3 years ago | 0

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How I can check if planes are parallel to each other in 3d?
planes(:,:,1) = [0 3 3; 0 0 3; 0 3 0; 0 0 0; 0 0 0]; planes(:,:,2) = [0 0 3; 3 0 3; 0 0 0; 3 0 0; 0 0 0]; planes(:,:,3) = [3 0...

3 years ago | 2

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What is the command for calculating expectation in MATLAB?
As a hint, generally, expectation and mean are terms with a similar meaning. Is there a function in MATLAB to compute a mean?

3 years ago | 0

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How can I restore image if I need to use command "interp2"
What does restore mean to you? Does it mean to some how recover the exact original image, after having interpolated it to some ...

3 years ago | 0

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Write a Gauss-Seidel preconditioner for ML
Learn what a sparse matrix is. And how to build them, how to use them. help sparse help spdiags The point being, you don't wa...

3 years ago | 0

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3D Surface of revolution from a 2D perimeter
Ok. (I should probably write code to do this in general, for any arbitrary polygon.) Quad elements. I'll show how to do it for ...

3 years ago | 0

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Solving a set of 8 non-linear equations using symbolic toolbox results in empty sym 0 by 1
NO. The equation POSSIBLY has a solution. In theory, it MIGHT have a solution. But having a theoretical solution does not mean i...

3 years ago | 0

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Find Indefinite Integral from Array Values
Sorry. there is no need for them to be exactly the same. Cumtrapz is a simple variation of a fixed stepsize Euler integration,...

3 years ago | 1

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How can I find a multiplication coefficient between two signal?
Your need is to solve the problem signal2 = constant*signal1 Where the variable "constant" is unknown. This is easy to solv...

3 years ago | 0

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Equation solution is not found for all array element
For SOME of these sub-problems, no solution was found. I would suggest that when the result from vpasolve is empty, you could ...

3 years ago | 0

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How to reduce dimensionality of a rectangular matrix
Your matrix has size 640000 by 288. So there are only 288 pieces of distinct information in your data. You CANNOT use PCA to do ...

3 years ago | 0

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Symbolic acos( cos(theta) ) does not return theta.
Is it true, that acos(cos(theta)) ALWAYS returns theta? TRY AN EXAMPLE. acos(cos(10)) So it is not true. It works the other wa...

3 years ago | 0

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curve fitting of two equation to two data sets simultaneously
Are the values of x the same for the two vectors y1 and y2? You don't show any data, so it is difficult to help more, as there ...

3 years ago | 0

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Create a single variable to store multiple correlation coefficients
A = rand(300,7); B = rand(1,300); C = corrcoef([A,B']); C = C(8,1:7) The correlation coefficiens of each column of A, agai...

3 years ago | 1

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How do I remove every row that has a zero in it?
TSLA = rand(366,7); TSLA(TSLA(:,4) == 0,:) = []; One line. No loops.

3 years ago | 0

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Creating a mxn matrix that is all zeros except for the middle row and middle column which are 1s
Clearly a homework assignment. But now long since past, and with multiple answers, most of which are not in one line. However, s...

3 years ago | 1

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find the index number using bsxfun command
But why would you use bsxfun at all to do this? A = [12 13 15 1]; B = [1 2 12 15 10 13 11 14 3 4 5 6 7 8 9 16]; Use ismember ...

3 years ago | 0

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How can I rearrange equations to general form?
syms x y z eqn1=x+y+5==-z Nothing stops you from doing it yourself. For example, I might do: eqn1 = eqn1 + z Or, you can ev...

3 years ago | 0

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Inverse computation with a starting guess
It is often the case that someone THINKs they need a matrix inverse, yet they don't. And since you don't know if you can do this...

3 years ago | 1

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Vectorization approach to find matching elements in a matrix.
The part of your code that is a serious problem is where you build the arrays by growing them at each step. This is a really bad...

3 years ago | 0

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Please how can I calculate the values of this finite sum of numbers in fully sequential , I'm finding it difficult
Easy peasy. sumof4thpowers = @(N) nchoosek(N+1,5) + 11*nchoosek(N+2,5) + 11*nchoosek(N+3,5) + nchoosek(N+4,5); For example: s...

3 years ago | 0

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optimization in smart energy management system.I have used MILP algorithm but i got infeasible solution no point satisfy the constraints.how could i sort out these issues.
No solution means exactly what it sounds like. NO solution. And for this class of problem, if it tells you that NO solution exis...

3 years ago | 1

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How to find derivatives using the diff command
There are two versions of diff in MATLAB. One operates on numeric vectors and arrays. It simply subtracts each number from the o...

3 years ago | 0

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Sum two matrices shifted by a non integer number?
There is no magic, whereby you can do things that take computational time, and do them instantly. What you want to do is implic...

3 years ago | 0

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Falkner-Skan code
You write: tau = (mu/(2*delta_y))*(4*un,2-un,3) But what des that mean to you? Is the fragment (4*un,2-un,3) intended to be...

3 years ago | 0

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sqrtm vs chol to produce draws the multivariate normal distribution
Don't bother. sqrtm also can have a similar problem, but you won't like what it does either! For example: A = rand(3,2); A = A...

3 years ago | 1

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How to get tangent line from a point not on the curve
The curve is: syms x y x0 F(x) = 945.75*x.^0.1002; A line tangent to the curve at any spcific location x0 would be simple to ...

3 years ago | 1

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Solving systems of trig equations
My gut says no symbolic solution will exist. But that does not mean my gut is accurate here. First, I would throw pencil and pap...

3 years ago | 0

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Merging piecewise polynomial (pp) structures
Is there any method to "merge" two PP functions? Well, no. Should there be one? I've been using and writing splines tools for 40...

3 years ago | 0