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The equation:
$$\dot{x} = f(x),\space x\in \mathbb{R},\space \text{where} \space f\begin{pmatrix}x_1\\x_2\end{pmatrix} = \begin{pmatrix} 3x_1^2 + 7x_1x_2 + x_1 + 2x_2^2 -x_2\\ -12x_1^2-16x_1x_2-3x_1 -x_2\end{pmatrix}$$
I want to draw the plausible phase portrait for this whole system. Is there any software where I can draw this?
I already drew the phase portrait in a neighborhood of x*
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$\begingroup$Here it is in Mathematica's Streamplot command
You can also try Maxima, SAGE, PPLANE, Phase Portrait Generator or many others.
For example, many Computer Algebra Systems can also do these plots.
Lastly, you can try OCTAVE, which is a MatLab clone and here is a post (see answers) showing the commands Plotting Differential Equation Phase Diagrams and these answers.
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