\(QS31_{9}^{(1)}\)

Description

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

Phase Portrait

Phase Portrait Graphic Design

Topological Invariants

TCSPFin SepInf Sep
\(31\)\(511\)\(311011\)

Example

The quadratic differential system

\[\begin{cases} \dot{x} = (1-e) \, x^{2}+2 \, h \, x \, y+(n-1-2 \, h) \, y^{2} \\ \dot{y} = y+c \, (1-e) \, x^{2}+(2+2 \, h-n) \, (1-e) \, x \, y-2 \, c \, x \, y+(c-2-2 \, h+2 \, n) \, y^{2} \end{cases}\]

with parameters: \(h = \frac{3}{100}, \quad c = \frac{-9}{10}, \quad n = -1, \quad e = 0.00001\)

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