PyPlane is a free software for phase plane analysis of second order dynamical systems written for PYTHON >= 3.8 and PyQT5 (compare MATLAB's pplane). It is published under the GNU GENERAL PUBLIC LICENSE Version 3.

• Vector fields and streamlines for second order nonlinear dynamical systems of the form x'=f(x,y), y'=g(x,y)
• Forward and backward solution trajectories for arbitrary initial conditions in the phase plane
• Time dependent solutions x(t) and y(t)
• 3D visualization t(x,y)
• Nullclines
• Find equilibrium points and calculate the corresponding Jacobian
• Linearize a system around equilibrium points, characterize and plot eigenvectors
• Add arbitrary function into the phase plane area (i.e. contour lines of Ljapunov-functions)
• An optionally installed and accessible LaTeX/dvipng environment produces much prettier results in the linearization tabs. If no LaTeX is installed, the program is still fully functional.
• Several example systems are shipped with PyPlane. You find them in the directory library. Load them via "Open - From File" or by pressing STRG+O

Please don't hesitate to report bugs, comments, or suggestions!

PyPlane runs either natively in a fully functional Python environment under Linux/ Windows/ OSX or as a stand-alone executable under MS Windows.

If you have pip available in your Python installation PyPlane can be easily installed as follows:

1. Clone the repository
2. Change into the root directory of the repository
3. Execute pip install .

PyPlane can then be invoked from the command line by executing the command pyplane or via python -m pyplane

Note: When some important missing features are implemented PyPlane will be also available via PyPi.

If the following pre-requisites are fullfilled you may invoke PyPlane directly from the repository:

Pre-requisites:

• Python 3.8, 3.9
• NumPy (tested under version 1.20, 1.21)
• SciPy (tested under version 1.6, 1.7)
• Matplotlib (tested under version 3.3, 3.4)
• SymPy (tested under version 1.7, 1.9)
• PyQt5 (tested under version 5.13, 5.15)

Launch of pylane

1. Clone the repository
2. Change into the root directory of the repository
3. Execute python run_pyplane.py or python -m pyplane

If you do not have Python available on Windows you can use the stand-alone version. You just need to run the provided installer file PyPlane_Setup.exe. It will create a directory on your desktop in which all required files will be stored. A shortcut for launching PyPlane will be placed on the desktop. No modifications in the system registry will be done. As in the native Python version, a functional LaTeX installation will produce better formatting results in the linearization tabs. However, even without LaTeX the program is fully functional.

Double-click on the PyPlane icon on the desktop in order to launch the application. Start-up may take some time.

The last version of this program which is fully compatible with Python 2.7 is version 1.1 .