KiwiCalc

Write mathematics naturally in Python.

KiwiCalc is a Python mathematics library built around readable, math-like expressions. It combines symbolic expressions, equation solving, numerical methods, geometry, linear algebra, plotting, probability, sequences, and printable worksheets behind one approachable API.

Why KiwiCalc?

Python is excellent for numerical work, but sophisticated mathematical expressions can become difficult to read and manipulate. KiwiCalc lets you construct expressions with familiar notation, substitute values, simplify them, convert them to callable functions, solve equations, and visualize results.

import kiwicalc as kw

x = kw.Var("x")
expression = x**2 + 6*x + 8

print(expression)                         # x^2+6x+8
print(expression.when(x=2).try_evaluate())  # 24
print(kw.solve_quadratic(1, 6, 8))       # (-2, -4)

Installation

Install the latest published version from PyPI:

python -m pip install kiwicalc

KiwiCalc supports Python 3.8 and newer.

Quick tour

Expressions and functions

import math
import kiwicalc as kw

x = kw.Var("x")
wave = kw.Sin(x) + kw.Cos(x)

print(wave.when(x=math.pi).try_evaluate())

parabola = kw.Function("f(x) = x^2 + 2x + 1")
print(parabola(3))  # 16

Equations

import kiwicalc as kw

print(kw.solve_linear("3x + 5 = 8"))
print(kw.solve_quadratic(1, 6, 8))

system = kw.LinearSystem((
    "x + y = 5",
    "2x - y = 1",
))
print(system.get_solutions())

Linear algebra and geometry

import kiwicalc as kw

matrix = kw.Matrix([[1, 2], [3, 4]])
vector = kw.Vector([3, 4])
point = kw.Point2D(2, 5)

print(matrix.determinant())
print(vector.length())
print(point)

Plotting

import kiwicalc as kw

x = kw.Var("x")
(kw.Sin(x) + 0.25*x).plot(start=-10, stop=10)

What is included?

• Symbolic monomials, polynomials, fractions, roots, logarithms, trigonometry, factorials, and composite expressions
• Linear, quadratic, cubic, quartic, polynomial, and system solving
• Numerical root-finding, integration, differentiation, and optimization methods
• Callable functions, function collections, and function chains
• Matrices, vectors, points, lines, circles, surfaces, and point collections
• Two- and three-dimensional plotting with Matplotlib
• Arithmetic, geometric, and recursive sequences
• Probability trees
• PDF exercise and worksheet generation
• JSON serialization for supported expression types

Documentation and learning resources

• Full documentation
• Official website
• Google Colab examples
• YouTube channel

Development

Create an isolated environment and install the project with its development tools:

python -m venv .venv
# Windows PowerShell: .\.venv\Scripts\Activate.ps1
# macOS/Linux: source .venv/bin/activate
python -m pip install --editable ".[dev]"
python -m pytest --cov=kiwicalc --cov-report=term-missing

Pull requests and pushes to main run the test suite on Linux and Windows. Published GitHub Releases are built, validated, and uploaded to PyPI through Trusted Publishing when the release tag matches the version in pyproject.toml.

Security note

KiwiCalc currently compiles some math-like expression strings into Python callables. Only evaluate expression strings from sources you trust; do not pass untrusted user input directly into the parser.

License

KiwiCalc is available under the MIT License.