It will soon be illegal for New York educators to carry firearms at school, thanks to a gun control package state legislators passed on Tuesday—the first the state has seen since 2013. Also included: new laws that enable the courts to determine if a person poses too much of a threat to own guns or have them in their home, extend the waiting period on gun purchases, ban bump stocks, and more. [ more › ] Gothamist http://bit.ly/2D3H3WX January 30, 2019 at 01:48AM
Van der Pol’s differential equation is The equation describes a system with nonlinear damping, the degree of damping given by μ. If μ = 0 the system is linear and undamped, but for positive μ the system is nonlinear and damped. We will plot the phase portrait for the solution to Van der Pol’s equation in Python using SciPy’s new ODE solver ivp_solve . The function ivp_solve does not solve second-order systems of equations directly. It solves systems of first-order equations, but a second-order differential equation can be recast as a pair of first-order equations by introducing the first derivative as a new variable. Since y is the derivative of x , the phase portrait is just the plot of ( x , y ). If μ = 0, we have a simple harmonic oscillator and the phase portrait is simply a circle. For larger values of μ the solutions enter limiting cycles, but the cycles are more complicated than just circles. Here’s the Python code that made the plot. from scipy import linspace from ...
Comments
Post a Comment