Answered
Monte Carlo integration (hit or miss) to find the area of a circle of radius R
You compare the area of the square with side length R and corner points (0,0), (R,0), (R,R) and (0,R) with the area of the quart...

1 year ago | 0

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Answered
Finding parameters by fitting data to a system of ODEs with lsqnonlin
syms T1(t) T0(t) s d g eqn1 = diff(T0,t) == s - (d+g) *T0 ; eqn2 = diff(T1,t) == 2*d*T0 + (d-g)*T1; sol = dsolve([eqn1,eqn2])...

1 year ago | 1

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Can pdepe solve a system of two second-order equations?
Goto https://uk.mathworks.com/matlabcentral/fileexchange/97437-pde1dm download the code, goto folder "documents" and study ex...

1 year ago | 0

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Answered
Error in flood_algorithm_rtc_pv (line 22) best_fitness = objective_function(best_solution, V_data, I_data); i don not understand this error
V_data and I_data must be of the same size. This is not the case in your code.

1 year ago | 1

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Answered
Issues solving a system of 2, second order, differential equations with ode45
Replace Cd = 0,45 ;% drag coef aircraft [-] rho_Air = 1,2 ...

1 year ago | 2

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Answered
simulating rolling 1 and 2 dice
You get a discrete pdf and cdf for the one and two dice-roll experiments you describe. So it doesn't make sense to smoothe resul...

1 year ago | 0

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Very new to this and need help making a contour plot that shows correlation between weight of powder, bullet seating depth, and group size.
What is the problem using the contourf command ? All you need is the matrix MOA - I created it using random numbers. Varget = 4...

1 year ago | 0

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Hello everyone, can anyone provide me the matlab code of FD SLIC algorithm or FM SLIC algorithm
https://uk.mathworks.com/matlabcentral/fileexchange/50184-slic-superpixels-for-e-cient-graph-based-dimensionality-reduction-of-h...

1 year ago | 1

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Eliminate for-loop in recursive computation?
pn_out = cumprod(fact).*(-y).^(m+1) But I'm not sure this will be faster than your loop, especially y.^(1:n) compared to a recu...

1 year ago | 0

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Answered
What happens if I set both RelTol and AbsTol for ODE45 and/or both TolX and Tolfun for FSOLVE?
Do these functions refine steps, etc. until both requirements are satisfied or only one of them? Both. Read about error contro...

1 year ago | 0

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Which statistic is minimized in curve fitting app
My question is what parameter/statistic is minimized to make a fit? SSE (maybe weighted if you specify weights for the measurem...

1 year ago | 1

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Help with MATLAB symbolic toolbox
Can't you use "dsolve" ? If not, use % Find the value of C1 interm of C2 C1_sol = vpa(solve(yp, C1),4) % Sub C1 into equat...

1 year ago | 0

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Answered
Find limits satisfying a condition on an integral
x = linspace(0, 2*pi, 20); y = sin(x); lowLimIndex = 1; target = 2; [~,upLimIndex] = min(abs(cumtrapz(x(lowLimIndex:end),y(l...

1 year ago | 0

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Answered
How plot density of function ?
Your function only depends on x, not on x and y. I'm not sure how you want to make it 2d. Thus I simply defined g(x,y) = f(x)*...

1 year ago | 1

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Problem with lsqnonlin and error function implementing a bovine pericardium constitutive model
strain(1) = 0 - thus you must remove the first data point since you divide by strain(i). Maybe your model function does not all...

1 year ago | 1

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Error on Symbolic calculation : "Empty sym : 0-by-1"
v1 = [393 393 393 393 393 393 393 393 393 393 ; 3850 4340 4760 5320 5740 6160 6580 7140 7980 8960]; v2 = [408 408 408 408 408 4...

1 year ago | 0

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Erron on Symbolic calculation [Case 2] : "Empty sym : 0-by-1"
If Λ is some kind of maximum likelihood function you try to maximize, I suggest you use "mle". We had this problem already - I ...

1 year ago | 0

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Answered
cosine of a matrix returns weird values.
"cos" and "tan" can be applied to angles in radians, not in degrees. Use "cosd" and "tand" instead.

1 year ago | 0

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Answered
How can I use Createpde to solve a fourth degree partial differential equation?
You have a system of two second-order differential equations. Thus instead of defining one equation, you have to define two and ...

1 year ago | 1

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mono- objective optimization and multiopjective optimisation, I would like to use GA with option but there is a fault that I can't to resolve
You mean objective = @(x) 1.002 - ((1 - exp(-0.00003 * x)) ./ (0.00003 * (x + 1.5) + 0.00063 * (1 - exp(-0.00003 * x)))); a = ...

1 year ago | 0

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How to place random CNT's in a box domain with random curves and orientation ?
https://uk.mathworks.com/matlabcentral/fileexchange/93250-generate-thick-fibers?s_tid=srchtitle

1 year ago | 0

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how to use fmincon to optimize a functio with more than one control vector where the control vectors used in constrains also?
If all three vectors/matrices are to be treated as solution variables for "fmincon", use v = [p(:);X(:);L(:)] It's useful to t...

1 year ago | 1

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Double Integration of Numeric Data - Acceleration -> Displacement
Assuming x(0) = v(0) = 0 in both cases, I get load("A2.mat") load("A9.mat") a2 = Datashort1; a9 = Datashort21; figure plot...

1 year ago | 0

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Find real valued parameters of a complex equation/model by using optimization or curve fitting.
I don't know if this helps to get better results, but of course you have to fit real and imaginary part of mu_eff simultaneously...

1 year ago | 0

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Answered
Storing while loop results in an array and plotting
Why do you think the results you get from the second part of your code are wrong ? g = 10; y(1) = 100; v(1) = 0; t(1) = 0; ...

1 year ago | 0

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Answered
how to solve this error? Objective function is returning undefined values at initial point. FSOLVE cannot continue.
In the computation of c0,...,c10, you divide by x(3),...,x(13), thus by 0 because x0 = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] . After ...

1 year ago | 0

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4th order Runge - Kutta vs. 4th order Predictor - Corrector
%--- Exercise 1 - A %--- Solving the diff. eqn. N'(t) = N(t) - c*N^2(t) with c = 0.5 using %--- Euler's method, Runge - Kutta ...

1 year ago | 0

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Answered
4th order Runge - Kutta vs. 4th order Predictor - Corrector
For k>4, the variable RKN should no longer appear in the equations PredN(k) = PredN(k-1) + h/24*( 55*f(t(k-1),RKN(k-1)...

1 year ago | 0

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Runge - kutta 4th order method for two different steps
y(j+1) = y(j) + h(i)*(K1 + K4 + 2*(K2 + K3))/6; instead of y(j+1) = y(j) + (K1 + K4 + 2*(K2 + K3))/6;

1 year ago | 0

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Answered
Error using surf (line 71) Z must be a matrix, not a scalar or vector.
Works for me (assuming that FL_hat is 1001x1001 in your case): alpha = linspace(0, 2*pi, 51); beta = linspace(0, 2*pi,21); FL...

1 year ago | 0

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