How to vectorize or speed up ODE solver with vector ?
I would like to vectorize or speed up ODE solver with vector E? This is extremely slow following this routine. nTime ...

4年弱 前 | 0 件の回答 | 0

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How to take FFT inside ode function ?
Matlab is solving ode point by point in t . I want to take FFT inside the function myode. It can taken outside but the way I...

4年弱 前 | 0 件の回答 | 0

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How to properly take derivative of discrete data ?
Taking derivative of discrete data requires some fitting and then using the b-form of the polynomial. How to make a 'good' fi...

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How to make arrows in quiver plot visible ?
How to make the arrows some what more proportional and look like arrows ? The matrices are attached. A = load(A.m...

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How to select element of matrix that is created with function handle ?
Let say we have matrix defined as A = @(a,n) [a 1 2+1i n*a; 0 1 3+n*1i a; a^2 0 1 a; a 0 0 a]; M1 = @(a)eye(4,4); f...

4年以上 前 | 2 件の回答 | 0

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How to find zeros of determinant having complex parameter ?
How to find the zeros of the determinant of 4x4 matrix M which is multiplication of N complex square matrices An containing para...

4年以上 前 | 1 件の回答 | 0

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How to solve (find zero) of nonanalitical function fzero or fsolve ?
I have a vector y(x) that does not necessarily have point on y = 0 axis (and is not analytical function). How can I solve (f...

4年以上 前 | 1 件の回答 | 0

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How to implement conformal transformation that wrap 2D image around a circle?
How to transform rectangular image to image that is bent at certain radius? On the plot the center line follows the radius whic...

5年弱 前 | 1 件の回答 | 0

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How to find the index of the closest value to some number in 1D array ?
How to find the index in 1D array that has closest value to some number ? val =-1.03 val1 = 1.04 x = -10:0.009:10 ...

5年弱 前 | 2 件の回答 | 0

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How to integrate the following function ?
<</matlabcentral/answers/uploaded_files/27869/dn.jpg>> How would you integrate this function ignoring the rect ? dx dz a...

5年弱 前 | 0 件の回答 | 0

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Could exponent of an array be inproved in speed ? Maybe mex file with exp function (reduced accuracy) for windows 64 bit.
Could this line of code be improved in speed ? MM is an array 512x512^2 elements. MM =ones(512^2,512); tic; exp(1i*(MM)...

5年弱 前 | 1 件の回答 | 0

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Could you please compile this as mex for windows 64 bit ? I can not run the compiler. Faster exp function with reduced accuracy.
Code for Exp function with reduced accuracy. I can not compile it. Code from <https://www.mathworks.com/matlabcentral/news...

5年弱 前 | 1 件の回答 | 0

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How to vectorize sum of scaled matrices ? Or is there matlab function for irregular inverse dft ?
I am trying to inverse transform function on irregular grid. Is there matlab function for irregular inverse dft ? I would...

5年弱 前 | 1 件の回答 | 0

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How to call element from vector out of t = @(theta) x*cos(theta)-y*sin(theta);
x = linspace(1,10,10); y=x; t = @(theta) x*cos(theta)-y*sin(theta); t(0.1) will give me vector. How to get element 5 ...

5年弱 前 | 1 件の回答 | 0

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How to vectorize loop of fft ?
How to vectorize a for loop of fft ? clear all W = ones(1,100)*1.5; y(1:200,1:100) = 0.3; ...

5年弱 前 | 1 件の回答 | 0

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How to store 1x3 vectors in (n,m) position of 2D matrix in a for loop ?
How to build nested array of 1x3 vectors in the (n,m) posision of 2D matrix in a for loop? And then how to access the n,m vec...

5年弱 前 | 0 件の回答 | 0

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Phase retrieval via SDP (semidefinite program)
I would like to have phase retrieval of test picture 2D let say phantom X = phantom('Modified Shepp-Logan',200); X =...