Tag Info

Shape of a boomerang

I do not clearly understand your question. However, if you want to plot the shape of a boomerang use the following code. ...
• 2,446

Galactic rotation speed

We can solve this problem using colocation method with Euler wavelets ang Gauss quadrature rule. First we define interval $0\le R\le Rmax$ and map interval $(0,R)$, on ...
• 45.4k

Solution of an integral equation

To solve this problem we can use iterative method described here. Unfortunately two conditions at $x=\pm \infty$ are not enough to define unique solution. Numerically we can define 2 solutions as ...
• 45.4k

Shape of a boomerang

Based on @user84456's helpful answer we can evaluate the parameters needed for the simulation (see my comment ) ...
• 54.1k
Accepted

How do I take the integral of a real number over a complex region?

In calculus class we called the first three TeX'ed lines in the OP, the method of substitution. It's not particularly connected with complex numbers. It's just that your equation has an ...
• 237k

• 3,782

How do I take the integral of a real number over a complex region?

May be ClearAll["Global`*"] ode = D[f[ τ ],τ]==A; sol = DSolveValue[ode,f[τ],τ] sol = sol/.{τ->I*r,C[1]->C[1]*I} Simplify[sol]
• 145k
Accepted

Galactic rotation speed

Here my third answer which solves case R==25 . This approach uses an interpolation-function (instead of wavelets or FEM) to describe the unknown function ...
• 54.1k

Galactic rotation speed

modified: Case Rmax==25 Inspired by the interesting discussion with Alex I found a direct approach, using a simple polygonal ansatz( borrowed from FEM). It solves the original integralequation, ...
• 54.1k

Galactic rotation speed

Here I 'll show an iterative solution. First the integralequation is differentiated D[....,R] . This finally gives ...
• 54.1k
Accepted

...
• 159k

Write Integral in Ostrogradsky's Method Form

Defining a module to perform and display the Ostrogradski method ...
• 159k
Accepted

How to speed up this integration?

Assuming m==h and a<0<q Mathematica 12.2 states non-convergent integral: ...
• 54.1k

Integro-differential equation with double integral

This problem can be solved with the Euler wavelets collocation method even in v.8 as follows ...
• 45.4k

• 26.7k
Accepted

Problem Encountered when Solving a System Consisting of Two PDEs and an ODE in a Semi-NDSolve-based Approach

This problem can be solved with using implicit Euler for time step and linear FEM for space. This method described, for example, here and here. First we transform equations to the system of ODEs and ...
• 45.4k

Asymptotic volume of intersection of n-cube with n-sphere

Using angles $\theta$ indexed by their power in the volume element with radius $r$ and equatorial angle $\phi$ ...
• 3,782
1 vote

Partial integro-differential equation

modified Try Galerkin method using MeshElementInterpolation: First we set B=1 by choosing an appropriate time scale. ...
• 54.1k
1 vote

How to solve the integral equation?

For small set of equations we can solve this problem using FindRoot (without error messages) as follows ...
• 45.4k
1 vote

Integration by Numerical Methods

Expand your expression into a sum of simple fractions and integrate step by step over the different variables \text{df}=\frac{e^{-\frac{\text{Ep}^2+\text{Eq}^2+p^2+q^2}{2 \sigma ^2}} \left(\left((\...
• 3,782

Only top scored, non community-wiki answers of a minimum length are eligible