sympy_equation 1.3.0

Equations that can be algebraically manipulated.

sympy_equation

This package defines relations that all high school and college students would recognize as mathematical equations, consisting of a left hand side (lhs) and a right hand side (rhs) connected by the relation operator "=". This is implemented by the Equation class, which also supports mathematical operations applied to both sides simultaneously, just as students are taught to do when attempting to isolate (solve for) a variable. Thus the statement Equation/b yields a new equation Equation.lhs/b = Equation.rhs/b.

The intent is to allow using the mathematical tools in SymPy to rearrange equations and perform algebra in a stepwise fashion using as close to standard mathematical notation as possible. In this way more people can successfully perform algebraic rearrangements without stumbling over missed details such as a negative sign.

A simple example as it would appear in a Jupyter notebook is shown immediately below:

In IPython environments (IPython, Jupyter, Google Colab, etc...) there is also a shorthand syntax for entering equations provided through the IPython preparser. An equation can be specified as eq1 =@ a/b = c/d.

If no Python name is specified for the equation (no eq_name to the left of =@), the equation will still be defined, but will not be easily accessible for further computation. The =@ symbol combination was chosen to avoid conflicts with reserved python symbols while minimizing impacts on syntax highlighting and autoformatting.

More examples of the capabilities of sympy-equation are here.

Development and Support

If you feel like a feature could be implemented, open an issue or create a PR. Implementing new features and fixing bugs requires time and energy too. If you found this module useful and would like to show your appreciation, please consider sponsoring this project with either one of these options:

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Installation

sympy_equation can be installed with pip or conda.

pip install sympy_equation

Or

conda install -c conda-forge sympy_equation

Customizing the module

equation_config is an object containing a few properties to customize the behaviour of the module:

from sympy_equation import equation_config

Arguably the most useful options are :

• equation_config.integers_as_exact (default is False). When it's True and we are running in an IPython/Jupyter environment, it preparses the content of a code line in order to convert integer numbers to sympy's Integer. In doing so, we can write 2/3, which will be converted to Integer(2)/Integer(3), which then SymPy converts to Rational(2, 3). If False, no preparsing is done, and Python evaluates 2/3 to 0.6666667, which will then be converted by SymPy to a Float.
• equation_config.show_label (default is False). When it's True, a label with the name of the equation in the python environment will be shown on the screen.

Check out the documentation to read more about these and other options.

Differences between sympy_equation and algebra_with_sympy

• sympy_equation is a fork of algebra_with_sympy, starting from the version 1.0.2.
• algebra_with_sympy installs a custom version of SymPy, which exposes the Equation class. The basic idea is to better integrate the Equation class with other SymPy functionalities. The downside is that as new releases of SymPy are available, the users of algebra_with_sympy must wait for a new version of the package to be released as well. Differently, sympy_equation is an external package that only depends on SymPy: as new releases of SymPy are available, sympy_equation will work with them right away. The downside is that it might not be as integrated with SymPy's functionalities as one would like it to be.
• algebra_with_sympy exposes the algwsym_config object to customize the behaviour of the module. Similarly, sympy_equation exposes the equation_config. The available options are very similar, but their default values are often different.
• algebra_with_sympy overwrites the default behaviour of SymPy's solve() and solveset() in order for them to return sets of solutions. This can be annoying if you are used to the SymPy's way of doing things. Differently, sympy_equation doesn't change the behaviour of these functions, rather it extends it in order to deal with the Equation class.