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Questions tagged [nonlinear-equation]

79 questions
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Find zero of a nonlinear equation using Julia

After a process usyng the SymPy in Julia, I generated a system of nonlinear equations. For the sake of simplicity, I am going to put an approximation here for the case of just a non-linear equation. What I get is something like this equation: R =…
Fam
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How to solve an overdetermined non linear set of equations numerically in python?

I am trying to solve a system of 4 exponential equations with two variables. However If I use fsolve python will only allow me two use as many equations as I have variables. But as I have infinitely many pairs of solutions (if only two equations are…
user21056350
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Non-linear equations in GEKKO with constant input range and iterative initial values

I'm trying to solve non-linear equations in GEKKO using bounds and initial values. The following example illustrates two main problems I'm trying to solve for a larger system of non-linear equations. from gekko import GEKKO import numpy as np m =…
itedin
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Solving an uncomplete nonlinear system of equations with Z3

I am trying to make a solver for nonlinear system of equations using the Z3 library in c++. It will exists with multiple equations and variables. Depending on previous steps in my software, it could be that some variables are unknown. When too many…
TijsVP
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Common tangent using python

I am trying to find a common tangent to two curves using python but I am not able to solve it. The equations to the two curves are complicated that involve logarithms. Is there a way in python to compute the x coordinates of a tangent that is common…
Sonic Sharma
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Is there a way to solve a non-linear equation in nested arrays?

I want to solve for m the following equation numerically on Python: C_left = np.cosh(m*(T/2 - t))/np.cosh( m*(T/2 - T - 1) ). In this case, C_left is a nested array of floats with dimensions 15 x 47 and T = 48. My intend outcome is a nested array…
Jane
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solving a simple (?) system of nonlinear equations

I'm trying to solve a simple system of non-linear equations described in this post. The system is two equations with two unknowns p and q and a free parameter lambda: When lambda = 1 the system looks like this: There is a unique solution and it's…
invictus
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Runge-Kutta : error while solving a second order differential equation

I am trying to solve a third order non linear differential equation. I have tried to transform it and I've obtained this problem which is a second order problem: I am trying to implement a fourth order Range-Kutta algorithm in order to solve it by…
Wiss
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The difference between scipy.optimize.fsolve and sympy's solve functions

I am trying to figure out the differences between Optimize.fsolve and SymPys solve function? **Is there a difference in computation or are the constraints as to which method to use?**Is Scipy fsolve more accurate than Numpy solve function? The…
Mat
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Sympy's solve() function doesn't yield all the solutions

I need to solve the following nonlinear system of equations : I am using sympy's solve() function to obtain the solutions to the system of equations. Normally, solve() yields all the solutions. I have specified the values of the constants…
bubucodex
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How to solve nonlinear equations in LibreOffice Calc?

I want to solve an equation that is an integration of Miner and Wöhler formulas: \frac{n_1}{N_1} + \frac{n_2}{N_2} = 1 where: n1s are stored in column A (assume numbers in 10^6-10^8 range) n2s are stored in column B (assume…
Foad S. Farimani
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Array input signal for ODEINT solver in SciPy (nonlinear system)

I want to pass an array input signal to ordinary differential equations solver 'odeint' instead of defining a function. Much like the linear solver lsim : tout, yout, xout = lsim(sys, U=input_sig(time), T=time) Which is much more convenient than…
Nuopel
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Explicit Euler method is unable to complete the solution to a system of differential equations

I am trying to solve the following nonlinear system of differential equation with the explicit Euler method: x' = f1(x,y), y' = f2(x,y) And I know the fact that the curve corresponding to the solution must connect (x_{initial},y_{initial}) to (0,1)…
user280016
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true odds: sympy solver with multiple equations and variables

I'm trying to calculate the 3-way true odds based on given odds according to this methodology: I'm trying to do this with the python sympy module with the following code: x, y, z, p, q, r, n = symbols('x, y, z, p, q, r, n', real=True) odds =…
Max Mustermann
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MATLAB resolution of a 6-th order non-linear differential equation [stiffness]

I am currently trying to solve a non-linear differential equation of order 6 for a function F defined on : Or : With these following boundary conditions : And an additional integral condition that is written : I am using MATLAB in order to do so…
Wiss
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