# Questions tagged [matlab]

For mathematical questions about MATLAB; questions purely about the language, syntax, or runtime errors would likely be better received on Stack Overflow. MATLAB is a high-level language and interactive programming environment for numerical computation and visualization developed by MathWorks.

985 questions
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### Fast, vectorisable distance from points to ellipse

I am writing a program im Matlab to find ellipses in noisy XY data using a Random Sampling Consensus (RANSAC) algorithm. It basically samples enough points to define an ellipse and then determines the ...
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### Integrate $\int_{0}^{\infty }e^{-\lambda\pi\big( k_1(r) + k_2(r) -k_3(r)\big)}f(r)dr$

This is my Matlab code for the above function. Am I missing something? ...
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### How to use numerical solution in differential equation?

I have numerical solution for variable $p$ (as series of numbers), which I got through ode45 method in MAtlab. I need to calculate $u$, where $$u=\dfrac{r^2-1}{16}\dfrac{dp}{dz}$$ May I use my ...
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### Improving bad fit for data using Matlab

I am trying to fit some data to estimate model parameters in a system of 5 ODEs. I cannot get a good fit. First I tried using Matlab lsqcurvefit and I get a very ...
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### Comparing analytical Fourier transform with FFTs

This is related to my other question on Stackoverflow. From using the tables on Wikipedia or Mathematica I can prove that the Fourier transform of function $$f(t) = -i H(t) \exp(-(ia+b)t),$$ where $H$...
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### Scaling differentiation matrices

I have been using differentiation matrices to approximate solutions. However my matrices are defined on $x\in[a,b]$ which varies between $[-1,1], [0, 1], [-\pi,\pi]$ for different equations and which ...
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### Absolute Stability- Plot

Plot the region of absolute stability of the method $y_{n+2}-y_n=\frac{1}{2}h(f_{n+1}+3f_n)$ where $f_n=(y_n,t_n)$. The only thing I can think of to do is absolute stability with the test equation, ...
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### How to derive a diffusion tensor and stationary states given a Markov process transition matrix?

Let the transition matrix $P_{ij}$ represents the probability to move from state $i$ to state $j$. Now I would like to derive the diffusion tensor for this Markov process. Since I am not sure how ...
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### What is the correct way to add process noise nad ODE45 solver for continous system (Matlab)

In the tutorial, when white noise process is added to ordinary differential equations (ODE), the ODE becomes stochastic process. Then the stochastic process needs to be solved using Euler Maruyama ...
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31 views