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35
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nsolve is unable to find roots for nonlinear equations
I'm trying to solve a set of nonlinear equations to determine the fixed points using "nsolve" in sympy. I'm using initial guess for the set of equations but nsolve is not able to give any ...
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user5830353
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vote
2
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128
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graphing nonlinear systems of ODEs in python
the model Im trying to graph this model however I am just not sure whether my code is leading me to a reasonable solution:
import numpy as np
import matplotlib.pyplot as plt
from scipy.integrate ...
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162
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How fix error in Mathematica "NDSolve::ndsz: At t == ... step size is effectively zero; singularity or stiff system suspected" when using Manipulate?
I am trying to solve a nonlinear system of differential equations in Wolfram Mathematica using NDSolve and visualize the solution with Manipulate. However, I encounter the following error when running ...
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1
answer
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Solving a set of coupled ordinary differential equation representing the coupled Chua oscillator with solve_ivp
I am trying to write a python code to solve the ODE representing a coupled Chua oscillators. The set of ODEs can be found here.
The non-linear term is defined as f(x)
And the possible solution is ...
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SageMATH failed to solve ODE with Symbolic Integration
I'm trying to solve an exact integration of a nonlinear ODE using SageMath.
I'm trying to find time function $x = x(t)$ integrating ODE $\dot{x} = b(2+\sqrt(1-x^2))(1-x^2)$ with SAGEMATH code below:
t ...
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2
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81
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how to plot a nonlinear fit in ggplot
I am trying to add another study (Study 3) but it is a non linear equation. Is there a way I can add y = 841C^0.395 into ggplot so that it can be overlaid onto the other studies?
df <- structure(...
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60
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Anomally with nleqslv function in R
I am using nleqslv function in R to solve 10 equations. However, sometimes it gets stuck when it can't resolve some of the inputs. Here is an example of the code, please note that the for loop is ...
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1
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203
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Least_square inaccurate in chemical speciation
I'm having an issue using the least_squares function to solve a system of non-linear equation to obtain a chemical speciation (here of the system Nickel-ammonia). The system of equations is given here ...
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Least_square method for n=p equations/unknown resolutio: Bounds/constraints not respected on proposed solutions
As a Phd Student, working on non-linear problem i try to find solutions, with physical meanings over the following system:
Input variables are A, B, Cf, Jp, ks, Pp, R,T.
Output variables are : Jw,Js,...
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2
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257
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How to solve a system of nonlinear equations with Python?
I'm trying to solve this system of nonlinear equations with Python:
2y3 + y2 - y5 - x4 + 2x3 - x2 = 0
(-4x3 + 6x2 - 2x) / (5y4 - 6y2 - 2y) = 1
Here's my code:
from sympy import symbols, Eq, solve
x, y ...
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solution for a "highly" nonlinear simultaneous equation with R
This is the first time I'm trying to solve a set of "highly" nonlinear set of equations with R. Please see the following code. The goal is to find Le and c such that Sum_F=0 and Sum_M=0. ...
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2
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216
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What's the fastest way to find the approximate coordinates of a circle tangent to two other circles in Python?
I'm trying to write a piece of code that packs circles of differing radii efficiently into a square-shaped sheet. With the algorithm I'm using, I need to find the tangent between:
a circle with a ...
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Code for non-linear constraints in CPlex opl
`Can anyone help me to code this constraint in Cplex opl . It seems to be nonlinear constraint but I do not know how to convert to linear constraint correctly:"enter image description here
l_jt_y[...
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1
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160
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Non-linear regression analysis with a floor function on (X)
I have created a data set to understand better an equation and apply it to predict behavior.
The equation is y = 10/(1+k*⌊((x/t)^s)⌋).
To create the data set and see if it is working properly, I did ...
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1
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113
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Finding symbolic solutions to nonlinear system of algebraic equations using Sympy
Here are a system of two nonlinear equations :
In an answer to a previous question it has been shown that this system of equations doesn't possess explicit solutions(here). But it is also noted that ...