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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)

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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 ...

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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...

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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 ...

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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...

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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...

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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...

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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...

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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...

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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,...

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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 %...

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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)....

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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 ...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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...

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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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