Answered
the integral of the Bessel function in Matlab
Seems there is no analytical solution for this integral (see MATLAB output above). Give values to the variables and use numeric...

4 years ago | 0

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Answered
Integrating this function and trying to solve for a variable displays errors!
L = 1;E = 1;I = 1;F=1; func = @(initial) L/sqrt((E*I)/(2*F)) - integral(@(theta)1./sqrt(cos(initial)-cos(theta)),initial,pi/2);...

4 years ago | 1

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Answered
My plot is empty...?
Change x = 15 : 1 : 50 ; to x = (15 : 1 : 50).' ;

4 years ago | 0

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Setting up a problem in linprog
I think the whole procedure only makes sense if x1 is a subset of x2, but here we go: scale = 1.5; x1 = [0,4,6,10,15,20]*scal...

4 years ago | 1

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Answered
Summation of multivariable symbolic functions
Why do you want f to be a symbolic rather than a numerical function ? a = [3;5]; y = [-2;1]; x = [1;pi]; X = [3 4;-0.345 8];...

4 years ago | 1

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Answered
mpower doesn't work with symbolic matrix
A = sym('a%d%d', [2 2]); A^2

4 years ago | 0

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create a sparse multidimensional matrix
i(1) = 3; j(1) = 1; v(1) = 1.0; i(2) = 7; j(2) = 2; v(2) = 1.0; i(3) = 11; j(3) = 3; v(3) = 1.0; m = 12; n = 3; A = s...

4 years ago | 0

Answered
Use lsqnonlin to optimize parameters to fit the property of a function
lsqnonlin slightly changes the input to "fun" from the first to the second call, but does not recognize any change of the output...

4 years ago | 0

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lsqcurvefit requires all values returned by functions to be of data type double.
Setting y = e/f*sind(theta) makes no sense because this setup will have infinitely many solutions. Use a single parameter e ins...

4 years ago | 0

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Answered
Using Contourf to Create Contour Plot with XYZ Data
This will work, but I don't think the interpolation of the Z data fits your needs. x = [ 185 168 151 134 11...

4 years ago | 0

Answered
Inserting functions in a vector function
g = @(x) x.^2; f = @(x) x.^4; for i = 1:3 f = @(x) g(f(x)); v{i} = f; end x = 4; v{1}(x) v{2}(x) v{3}(x)

4 years ago | 0

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Answered
Relatively easy optimization problem in Excel it's hard to implement on Matlab
If you accept a MATLAB solution for this problem: min: norm(X*p-y) s.c. xt = data*w 0<=w<=1 w integer where p is (3x1) and...

4 years ago | 0

Answered
How to perform linear curve fitting based on distance from line instead of residuals
rng("default") t = rand(100,1); x = t/10 + randn(size(t))/10; y = 5*t + randn(size(t))/10; plot(x,y,'o') sol = fminsearch(@...

4 years ago | 0

Answered
Solution of two order differential equations; Fourth order Runge-Kutta method iteration
Running your problem with ODE45 gives your Runge-Kutta results. So the problem seems to be that your parameters are different fr...

4 years ago | 0

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Answered
How to perform linear curve fitting based on distance from line instead of residuals
The residuals are the sum of the vertical distances of the points from the line. If you want to consider the orthogonal distanc...

4 years ago | 0

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PERIMETER OF A 3D POLYGON WHICH DOES NOT LIE IN THE X-Y PLANE
The code should apply to your case: x = 3*cos(0:pi/20:2*pi); y = 3*sin(0:pi/20:2*pi); fn = cscvn([x;y]); % Compute enclosed ...

4 years ago | 1

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Answered
Initial Conditions not Generating on Graph
You plot "hs" for different values of "nd". So the initial condition for hs is always the same, namely 225 mm. I don't underst...

4 years ago | 0

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Answered
Nonlinear regression using lsqcurvefit
F = @(x,f) x(1)/2 * sin(x(2)*pi/2)./(cosh(x(2)*log(2*pi*f*x(3)))+cos(x(2)*pi/2)); instead of F = @(x,f)(x(1)./2)*(sin(x(2).*pi...

4 years ago | 0

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Answered
Problem with "if" command
Should be if PBtime_nb>PBtime_b instead of if PBtime_b>PBtime_nb;

4 years ago | 1

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Minimize distance between curves
Differentiating with respect to a, setting the derivative to 0 and solving for "a" gives a = sum_i (f_i*g_i) / sum_i (f_i^2) I...

4 years ago | 0

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Answered
How to make 2D matrix from 3D matrix to solve 2D nonlinear system?
The matrix you have to create and work with is a (sparse) matrix of size (125000 x 125000). The 3d matrix above (whatever it ma...

4 years ago | 1

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Use pdepe to solve an ode
So your equation is not a PDE, but a simple ODE. Either you try to artificially set du/dx = 0 at both ends and see whether the...

4 years ago | 0

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Projected curve lengths (XY,XZ,YZ) of 3D arcs
Then just set the coordinate of the plane you project on to 0 and calculate the arc length of the resulting projected curve. An...

4 years ago | 0

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Answered
Solving a system of PDE using pdepe
The error is solved, but I think the boundary conditions at the right end can't be set within pdepe. The condition set at the m...

4 years ago | 1

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Answered
optimization toolbox with fmincon
If you want to admit x,y and z to be complex-valued, you also have to change your objective function to be real-valued for compl...

4 years ago | 0

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How do I find the index of the first element equal to 0 for each row of a matrix in a fast way
[~,idx] = max(M==0,[],2) or idx = arrayfun(@(k)find(M(k,:)==0,1),1:size(M,1))

4 years ago | 0

Answered
Spline coordinates from spap2
x = -2:.2:2; y=-1:.25:1; [xx, yy] = ndgrid(x,y); z = exp(-(xx.^2+yy.^2)); sp = spap2({augknt([-2:2],3),2},[3 4],{x,y},z)...

4 years ago | 0

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Answered
How can the lqr function in matlab be modified so that the 2*x'Nu term in the cost function J be replaced with a scalar value?
I wonder why the integral should be finite if you replace 2*x'*N*u by a fixed scalar value. This scalar value must definitely be...

4 years ago | 0

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Answered
solve quadratic equation with matrix input variable
syms P N =2000:-50:50; guess = 2; for i=1:numel(N) n = N(i); eqn=((((1.3+(((17.5).*P)./(P+n./20))).^2)+((0.036.*P)....

4 years ago | 0

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Answered
estimation of probability density function
help ksdensity

4 years ago | 0