\(QS25_{2}^{(1)}\)

Description

Topological configuration of singularities: \(s,a;S,N,N\)

Phase Portrait

Phase Portrait Graphic Design

Topological Invariants

TCSPFin SepInf Sep
\(25\)\(40\)\(211101\)

Example

The quadratic differential system

\[\begin{cases} \dot{x} = y+a \, x^{2}+b \, x \, y+c \, x \\ \dot{y} = x^{2}+x \, y+y^{2}+d+e \, x+f \, (y+a \, x^{2}+b \, x \, y+c \, x) \end{cases}\]

with parameters: \(a = 0, \quad b = 2, \quad c = 0.001, \quad d = -0.00001, \quad e = -0.0007, \quad f = 0.0008\)

has the following phase portrait done with P4. If you want, you may download the P4 file here. Since the image is not clear enough, we have added a ZOOM of it.

The phase portrait appears in the following papers

Bifurcations in codimension 0