Answered

How to find the intersection of linear regression model and yline

Pretty boring data. T(:,1) = [0 1 2 3 4 5]; T(:,2) = [0 1 2 3 4 5]; P = polyfit(T(:,1),T(:,2),1) a = P(1) b = P(2) They...

How to find the intersection of linear regression model and yline

Pretty boring data. T(:,1) = [0 1 2 3 4 5]; T(:,2) = [0 1 2 3 4 5]; P = polyfit(T(:,1),T(:,2),1) a = P(1) b = P(2) They...

ungefär en månad ago | 0

Answered

Issue with solving ill-conditioned symbolic DAE system

You have a DAE, with a linear constraint system that happens to be ill-conditioned. I would try reducing the constraint system. ...

Issue with solving ill-conditioned symbolic DAE system

You have a DAE, with a linear constraint system that happens to be ill-conditioned. I would try reducing the constraint system. ...

ungefär en månad ago | 0

Answered

inv(A)*B*inv(A) or A\B/A, which is more accurate for a full rank A and half rank B

Why would you want to compute the inverse of A TWICE ANYWAY? Even using both slash and backslash is arguably a bad idea, since a...

inv(A)*B*inv(A) or A\B/A, which is more accurate for a full rank A and half rank B

Why would you want to compute the inverse of A TWICE ANYWAY? Even using both slash and backslash is arguably a bad idea, since a...

ungefär en månad ago | 0

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Answered

Finding accurate inverse of binary circulant matrix

Gosh. I thought that multiplying a matrix by its inverse gives an identity matrix. :) A = readmatrix('MixingLayer.xlsx','sheet'...

Finding accurate inverse of binary circulant matrix

Gosh. I thought that multiplying a matrix by its inverse gives an identity matrix. :) A = readmatrix('MixingLayer.xlsx','sheet'...

ungefär en månad ago | 0

Answered

Doing a Matlab update without charging

Is it a bad thing? Only in the sense that if your computer suddenly dies in the middle, the software may now be in a spot where ...

Doing a Matlab update without charging

Is it a bad thing? Only in the sense that if your computer suddenly dies in the middle, the software may now be in a spot where ...

ungefär en månad ago | 0

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Answered

Not able to plot a proper graph for the equation.

syms x y = (1*1*((25)-(x.^2)))/((x.^4)-((x.^2)*((1*(1.78))+(25)+1))+(1*(25))) First, where are the poles? A pole lives where t...

Not able to plot a proper graph for the equation.

syms x y = (1*1*((25)-(x.^2)))/((x.^4)-((x.^2)*((1*(1.78))+(25)+1))+(1*(25))) First, where are the poles? A pole lives where t...

ungefär en månad ago | 0

| accepted

Answered

How to find solution to system of 2 circle equations in Matlab?

Torsten has answered your question perfectly well, I think. No solution exists for that problem as posed. But suppose you had a ...

How to find solution to system of 2 circle equations in Matlab?

Torsten has answered your question perfectly well, I think. No solution exists for that problem as posed. But suppose you had a ...

ungefär en månad ago | 0

Answered

How to colour a portion of a curve by red and remaining by black

Plot it as TWO curves, both on the same figure, one in red, one in black. Use the hold command between the two calls to plot, s...

How to colour a portion of a curve by red and remaining by black

Plot it as TWO curves, both on the same figure, one in red, one in black. Use the hold command between the two calls to plot, s...

ungefär en månad ago | 0

Answered

Solve an ODE on a torus

Simple enough. Just transform the problem. So if [u,v] live on [0,1]x[0,1], then s = (cos(2*pi*u)+1)/2 t = (cos(2*pi*v...

Solve an ODE on a torus

Simple enough. Just transform the problem. So if [u,v] live on [0,1]x[0,1], then s = (cos(2*pi*u)+1)/2 t = (cos(2*pi*v...

ungefär en månad ago | 0

Answered

Problem with matrix dimensions

I'm not sure why you would use a Newton method to solve what solve will do directly, in an apparent algebraic form. beta1 = 0.0...

Problem with matrix dimensions

I'm not sure why you would use a Newton method to solve what solve will do directly, in an apparent algebraic form. beta1 = 0.0...

ungefär en månad ago | 0

Answered

Solve ill-conditioned linear systems

The determinant of a matrix is completely, totally irrelevant. Yes, I know you were taught that if it is zero, then the matrix i...

Solve ill-conditioned linear systems

The determinant of a matrix is completely, totally irrelevant. Yes, I know you were taught that if it is zero, then the matrix i...

ungefär en månad ago | 0

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Answered

Adjusting Convex Hull Area

I fail to see the issue. No, you cannot adjust how a convex hull computes the area. A convex hull does not see pixels. It sees t...

Adjusting Convex Hull Area

I fail to see the issue. No, you cannot adjust how a convex hull computes the area. A convex hull does not see pixels. It sees t...

ungefär en månad ago | 0

Answered

How to calculate real roots of a polynomial equation under square root ?

syms t real coupler_parametric=[5163136522924301/2251799813685248,... 2^(1/2)/2 - (8*t)/(t^2 + 1), - (4*(t^2 - 1))/(t^2 + ...

How to calculate real roots of a polynomial equation under square root ?

syms t real coupler_parametric=[5163136522924301/2251799813685248,... 2^(1/2)/2 - (8*t)/(t^2 + 1), - (4*(t^2 - 1))/(t^2 + ...

ungefär en månad ago | 0

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Answered

Find approximate solution of equation

Is there some general method, to ALWAYS be able to approximate the solution of a large system, and have a reliable result? No. O...

Find approximate solution of equation

Is there some general method, to ALWAYS be able to approximate the solution of a large system, and have a reliable result? No. O...

ungefär en månad ago | 0

Answered

[0:0.1:1] whys is not exactly 0.1 steps ?

Can you represent the number 0.1 exactly? Remember that MATLAB does not store the exact representation of numbers. Instead, it u...

[0:0.1:1] whys is not exactly 0.1 steps ?

Can you represent the number 0.1 exactly? Remember that MATLAB does not store the exact representation of numbers. Instead, it u...

ungefär en månad ago | 2

Answered

How to stop quadratic formula calculator from giving inverse outputs?

The roots of the quadratic you supply are indeed 6 and -3. roots([1 -3 -18]) So your code worked correctly. If you expected ...

How to stop quadratic formula calculator from giving inverse outputs?

The roots of the quadratic you supply are indeed 6 and -3. roots([1 -3 -18]) So your code worked correctly. If you expected ...

ungefär en månad ago | 1

Answered

hyperpca applied to a set of several hyperspectral images

You cannot combine multiple PCA analyses. Since each one requires the computation of the eigenvalues and eigenvectors of a matri...

hyperpca applied to a set of several hyperspectral images

You cannot combine multiple PCA analyses. Since each one requires the computation of the eigenvalues and eigenvectors of a matri...

ungefär en månad ago | 0

Answered

Simpson integral - problem with writing the formula

a is a scalar. At least, it should be, based on how you show the code was called. If so, then why have you done this? dI = f(a(...

Simpson integral - problem with writing the formula

a is a scalar. At least, it should be, based on how you show the code was called. If so, then why have you done this? dI = f(a(...

ungefär 2 månader ago | 0

Answered

If I have an array and I need to find an element in the array how do I go about it?

I think you are confusing things, not understanding there is a difference between the number 110, and the vector [1 1 0], and th...

If I have an array and I need to find an element in the array how do I go about it?

I think you are confusing things, not understanding there is a difference between the number 110, and the vector [1 1 0], and th...

ungefär 2 månader ago | 0

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Answered

Matlab Predict function is not efficient

No code is ever as fast as users want. If you know how to make it faster, then write your own version. If your version really is...

Matlab Predict function is not efficient

No code is ever as fast as users want. If you know how to make it faster, then write your own version. If your version really is...

ungefär 2 månader ago | 0

Answered

Equally spaced points along a nonlinear path

Simpler yet, just download my interparc from the file exchange. It allows you to do the operation in a variety of ways, using se...

Equally spaced points along a nonlinear path

Simpler yet, just download my interparc from the file exchange. It allows you to do the operation in a variety of ways, using se...

ungefär 2 månader ago | 1

Answered

Converting between x,y cartesian variables to angle in symbolic variables

No, the toolbox will never try to understand your equations, and then infer what the variables mean to you, and then perform sub...

Converting between x,y cartesian variables to angle in symbolic variables

No, the toolbox will never try to understand your equations, and then infer what the variables mean to you, and then perform sub...

ungefär 2 månader ago | 0

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Answered

how write a matrix with specific features

I think you are confused about what you can do with MATLAB. Those constraints simply tell you the associated matrix for the grap...

how write a matrix with specific features

I think you are confused about what you can do with MATLAB. Those constraints simply tell you the associated matrix for the grap...

ungefär 2 månader ago | 1

Answered

I have a nonlinear equation with a symbolic variable and cant solve it.

Look carefully at your problem. n = 2.1; alpha0 = 0; syms p alpha eqn = p^(n+1) - alpha0*p^n + p -(alpha0 + alpha) == 0 So ...

I have a nonlinear equation with a symbolic variable and cant solve it.

Look carefully at your problem. n = 2.1; alpha0 = 0; syms p alpha eqn = p^(n+1) - alpha0*p^n + p -(alpha0 + alpha) == 0 So ...

ungefär 2 månader ago | 0

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Answered

findging eigenvectors with eigenvalues

Most of the time when I see someone worry their eigenvectors are not correct, it is just because of a sign error on the eigenvec...

findging eigenvectors with eigenvalues

Most of the time when I see someone worry their eigenvectors are not correct, it is just because of a sign error on the eigenvec...

ungefär 2 månader ago | 1

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Answered

Library function log10 not found when using fit

x = rand(10,1);y = x + rand(10,1); fit(x,y,'log10') It is almost always, ALWAYS the case that when this happens, you were prev...

Library function log10 not found when using fit

x = rand(10,1);y = x + rand(10,1); fit(x,y,'log10') It is almost always, ALWAYS the case that when this happens, you were prev...

ungefär 2 månader ago | 1

| accepted

Answered

iterative estimation of eigenvalues and eigenvectors by the inverse power method. Your MATLAB/Octave code shouldn’t be hardcoded. ● Calculate the eigenvectors and eigenvalues

Let me guess, you have a problem with this matrix. Does the matrix have any special properties? What, for example, are the eige...

iterative estimation of eigenvalues and eigenvectors by the inverse power method. Your MATLAB/Octave code shouldn’t be hardcoded. ● Calculate the eigenvectors and eigenvalues

Let me guess, you have a problem with this matrix. Does the matrix have any special properties? What, for example, are the eige...

ungefär 2 månader ago | 0

Answered

using PCA to filter outliers in MATLAB

I've attached my quick shot at an n-dimensional outlier tool, based on Mahalanobis distance. I am pretty sure it has some seriou...

using PCA to filter outliers in MATLAB

I've attached my quick shot at an n-dimensional outlier tool, based on Mahalanobis distance. I am pretty sure it has some seriou...

ungefär 2 månader ago | 1

| accepted

Answered

How do I plot a symbolic equation that I have created?

By the way, there is NOTHING symbolic in the code you wrote. syms t % this makes t symbolic % no need to put decimal points ...

How do I plot a symbolic equation that I have created?

By the way, there is NOTHING symbolic in the code you wrote. syms t % this makes t symbolic % no need to put decimal points ...

ungefär 2 månader ago | 0

Answered

scatter command not working

(It is good you are using the tutorials.) But first, learn to read the error message, an important skill in using MATLAB, unless...

scatter command not working

(It is good you are using the tutorials.) But first, learn to read the error message, an important skill in using MATLAB, unless...

ungefär 2 månader ago | 1

| accepted