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in this code for finding root by newton raphson method i gave derivative of f in g. instead of giving derivative directly how can i get derivative using any code?
syms x f = x^4-x^2-80; g = jacobian(f); f = matlabFunction(f) g = matlabFunction(g)

circa un mese fa | 0

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how to plot two nonlinear functions
x = -10:0.1:10; y = 0:0.1:20; [X,Y] = meshgrid(x,y); Z1 = X.^2+X.*Y-10; Z2 = Y+3*X.*Y.^2-57; % Visualize the two surfaces ...

circa un mese fa | 2

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Using symbolic solver, I seem to not be able to get a system of equations that give me a desired answer. Does a solution not exist?
It's the same situation as in your other problem: https://uk.mathworks.com/matlabcentral/answers/2138791-how-can-i-find-a-uniqu...

circa un mese fa | 1

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2nd Order Polynomial Coefficient Solving
I don't see R in your regression equation T = a + b*P + c*S + d*S^2 + e*(S*P) + f*(s^2*P) And I assume that "s" means "S". M ...

circa un mese fa | 2

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limited integration with respect to x in Simulink
As far as I can see, the integral is of the form integral_{x=0}^{x=L} dx / (a*x+b) for some constant values a and b. The anti...

circa un mese fa | 0

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Routh-Hurwitz criterion
Roots of a general polynomial of degree 6 cannot be explicitly computed. You must give numerical values to a,b,c,d,e and f and u...

circa un mese fa | 0

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paretosearch does not satisfy nonlinear constraints
You may get feasible initial points if you run this code before calling "paretosearch" (maybe for different x0 to get several fe...

circa un mese fa | 1

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When does an ODE integrator reach the best numerical accuracy?
Solve the problem for different error tolerances and see when the solution stabilizes. If available, also test different solve...

circa un mese fa | 1

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Plot grraph , srink is problem
I don't know what you mean by "I want to change the Y axis value so that the box and plot on x -axis does concide". Maybe like...

circa un mese fa | 0

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double and triple integral for a complex function. I coded but did not get any output
According to the literature, the Monte Carlo Integration method seems to be the usual approach: https://iopscience.iop.org/arti...

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How to update a function with output from another function?
% Solve the coupled ODEs and PDE [t, y] = ode45(@(t, y) odes(t, y, R, C_p_gas, k_liner, k_CFRP, rho_liner, rho_CFRP, C_p_liner,...

circa un mese fa | 0

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Unable to recognise function from called script
The script should be t = [1, 2, 3, 4]; y = lab1_function(t,0.1) the function should be function y = lab1_function(t, c) y...

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I have matlab code, when i run the program i could 't get the values and also graph.Can u help me in this regards?
Don't solve the equations separately (first for T and C, then for f and h) , but all four together in one call to bvp4c. They a...

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How to Extract Delayed State Terms in a Model with Distributed Delay?
So in the distributed case you want to extract y2_delayed(t) = integral_{tau = t-1.5]^{tau = t-0.5} y2(tau) dtau thus the te...

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Solution of a 2nd order non linear implicit differential equation using ode15i implicit solver
% Initial conditions y0 = [0 2]; % initial displacement and velocity %yp0_guess = [0; 0]; % Initial guess for derivatives %...

circa 2 mesi fa | 0

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Different behaviour when using symbolic simplification on norm() for scalars and vectors?
If you want to define the norm of the difference of two real-valued n-dimensional vectors, use norm_x_minus_y = sqrt(sum((x-y)....

circa 2 mesi fa | 1

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Unable to perform assignment because value of type 'optim.problemdef.OptimizationExpression' is not convertible to 'double'.
If you use optimvars on the right-hand side of the assignment hapsCoreAvailability(coreIdx) = T_start + execTime; (T_start is ...

circa 2 mesi fa | 0

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Estimation the parameters of a non-linear equation
If only reproducing the x-P curve matters, you can use the following code. If the density of the x-values in certain regions sh...

circa 2 mesi fa | 0

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Find the combination that maximize the objective function values from the data set.
filename = 'Objective Optimization MATLAB.xlsx'; data = xlsread(filename); data(:,7:end) = []; n = 1; while(size(data,1) > 0...

circa 2 mesi fa | 0

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Source code for solving second order ODE/PDE using PINN
Why do you want to use code for partial differential equations if you have an ordinary differential equation to solve ? syms ps...

circa 2 mesi fa | 0

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To RESHAPE number of elements must not change
It means that the number of elements in the original and the reshaped array must be the same: a = rand(15,1); a_ok = reshape(a...

circa 2 mesi fa | 0

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how to modify code for distributed delay
r = 1.5; fun = @(t,x)[r*x(1)*(1-x(2));x(1)]; x0 = [0.5;0]; tspan = [0 20]; [t,x] = ode45(fun,tspan,x0); plot(t,x(:,1)) gri...

circa 2 mesi fa | 1

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Finding the closest coordinate from a surface plot based on a X, Y location
lat_GMM and lon_GMM are not within the rectangle in which data for z are supplied. In this case, interp2 returns NaN because i...

circa 2 mesi fa | 0

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Global stability of an epidemiology
clear; clc; % Define the parameters of the epidemic model alpha1 = 0.0444; % transmission rate alpha3 = 0.2; % fixed rec...

circa 2 mesi fa | 0

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How to fit kinetic model to estimate kinetic parameter from experimental data
I replaced C = b(11)-(0.9*y(2))-(0.947*y(3))-(0.9*y(4)/0.511)-(1.137*(y(1)-1.04)); by C = b(1)-(0.9*y(2))-(0.947*y(3))-(0.9*y...

circa 2 mesi fa | 1

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I am trying to solve the system of coupled partial differential equations described in the attachment using the function pdepe. My code runs into this error:
"pdepe" is a solver for parabolic-elliptic partial differential equations (with a second-order spatial derivative term modelling...

circa 2 mesi fa | 1

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How to input a novel boundary condition for a coupled PDE system
xOde = [0 1].'; % Define coupling points for ODE definition function [pl, ql, pr, qr] = PDE_PSw_EK_BC_2(xl, yl, xr, yr, t, v...

circa 2 mesi fa | 0

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quadprog output: this problem is non-convex
Maybe there are Inf or NaN coefficients in your A ? The following small example works. A = rand(53,66); [m,n] = size(A); opti...

circa 2 mesi fa | 0

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Problem with finding the global minimum with fmincon
What are x(1) - x(4) in your mathematical description ? In other words: What are your optimization parameters ? You don't defin...

circa 2 mesi fa | 0

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Why do my laptop and work computer produce different results when adding a small term to a matrix?
In the representation with 4 decimal places, the results don't seem to differ. But it's not unusual that computations on diffe...

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