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 ...