Any idea why dsolve in sympy 1.14 when given this ode Eq(x**a * y(x) + Derivative(y(x), (x, 2)),0) gives error TypeError: 'Symbol' object cannot be interpreted as an integer code from sympy import * x ...

I am trying to model a fatigue crack growth in Python using Paris’ law : da / dN = C ( DeltaK ) ^ m where : a = crack length N = load cycles C, m = material constants ( DeltaK ) = Y.( DeltaSigma ).( ...

I am trying to solve a convection-diffusion-reaction problem for a tubular reactor. The reaction governing the process is as follows: The method I chose to solve it is the line method, which consists ...

I would like to compute the residual of the numerical solution to an ordinary differential equation. Here is the code import numpy as np from scipy.integrate import solve_ivp def f(t, x): return ...

I’ve written a MATLAB implementation of an implicit Runge–Kutta method (Radau IIA). It behaves well on most test problems, but it refuses to converge on the following very stiff equation like y' = y^2 ...

I am trying to add a legend to each plot output of the ccl4model(ODE model) in the deSolve package using plot.deSolve and the legend method but it only appears on the last plot output of the model. I ...

I ended up trying to build a for-loop to achieve my end goal (running an ODE function modeling disease transmission through different scenarios/parameter sets in the most transparent way possible) but ...

I'm trying to simulate a satellite tracker. With ode45 I have de state of the satellite for each time and then convert position to Azimuth-Elevation local coordinates. If the object enters in the ...

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 ...

I am using the following code. How can I plot time (x-axis) vs C_WT (y-axis) line plots for different C_WT values as in vectorC_WT in a single graph in R ? kon_WT = 1 koff_WT = 10 R_WT = 20 ...

I'm modeling the spread of an infectious disease in R, and I need to loop the model through multiple sets of parameters. I have a working model so far (a dummy version is below), but only for a single ...

I am trying to solve two coupled differential equations in python using the solve:ivp() function from scipy.integrate but I get an unexplained gain on one of my terms that breaks the equation. It is ...

I composed the following ODE file: function [dndt,dmdt,dhdt,dVdt]=hh(n,m,h,V) C=1; GK=36; GNa=120; GL=0.3; EK=-72; ENa=55; EL=-49.4; dndt=(1-n)*alphan(V)-n*betan(V); dmdt=(1-m)*alpham(V)-m*...

Let us consider the following code: import sympy as sy import scipy as sc from sympy.physics.units.quantities import Quantity from sympy.solvers.ode.systems import dsolve_system from IPython.display ...

I am now struggling with a shooting method using python. The original question is ODE, with m=0 Here's my code, and I wonder why the graph would become flatter if the tolerence gets smaller. import ...