DynamicVector Python Module

DynamicVector is a Python class designed to combine the flexibility of Python lists with the computational efficiency of NumPy arrays. It allows for dynamic resizing, list-like manipulation, and full access to NumPy’s powerful numerical operations.

Features

• Dynamic Resizing: Automatically expands as new elements are appended or inserted, mimicking Python lists.
• NumPy Integration: Access to all NumPy array operations and methods via the view property.
• List-Like Functionality: Supports common list operations such as append, insert, and pop, making it highly versatile.
• Optimized for Performance: Takes advantage of NumPy’s speed and memory efficiency for handling large datasets.

Installation

Ensure that numpy is installed in your environment. If not, you can install it using:
(note, this module was only tested against numpy>2.0)

pip install numpy

To install the module

pip install --upgrade git+https://github.com/ScottBoyce-Python/DynamicVector.git

or you can clone the respository with

git clone https://github.com/ScottBoyce-Python/DynamicVector.git

and then move the file DynamicVector/DynamicVector.py to wherever you want to use it.

Usage

Below are examples showcasing how to create and interact with a DynamicVector.

Creating a Vector

from DynamicVector import DynamicVector

# Initialize with a list
vec = DynamicVector.from_values([1, 2, 3])  # integer vector with three values
print(vec)       # Output: DynamicVector([1, 2, 3])
print(repr(vec)) # Output: DynamicVector([1, 2, 3], dtype=int32)

Using NumPy Functions

# Access the underlying NumPy array via the 'view' property
print(vec.view)       # Output: [1 2 3]
print(vec[:])         # Output: [1 2 3] -> same as vec.view

# Perform NumPy operations
vec += 1
print(vec)            # Output: DynamicVector([2, 3, 4])

vec[1] = 99
print(vec)            # Output: DynamicVector([ 2, 99,  4])

vec[1:len(vec)] = 8   # set element 2 and 3 to the value of 8.
print(vec)            # Output: DynamicVector([2, 8, 8])

vec[:] = [2, 3, 4]
print(vec)            # Output: DynamicVector([2, 3, 4])

Appending and Adding Elements

# Append elements dynamically
vec.append(5)         # Fast operation
print(vec)            # Output: DynamicVector([2, 3, 4, 5])

vec.extend([7, 8, 9]) # Fast operation
print(vec)            # Output: DynamicVector([1, 2, 3, 5, 7, 8, 9])

# Insert at a specific index
vec.insert(1, 10)
print(vec)            # Output: DynamicVector([ 1, 10,  2,  3,  5,  7,  8,  9])

# Insert at a specific index
vec.insert_values(3, [97, 98])
print(vec)            # Output: DynamicVector([ 1, 10,  2, 97, 98,  3,  5,  7,  8,  9])

Popping Elements

# Remove and return the last element
print(vec)            # Output: DynamicVector([ 1, 10,  2, 97, 98,  3,  5,  7,  8,  9])
last_elem = vec.pop() # Fast operation
print(vec)            # Output: DynamicVector([ 1, 10,  2, 97, 98,  3,  5,  7,  8])
print(last_elem)      # Output: 9

third_element = vec.pop(2)
print(vec)            # Output: DynamicVector([ 1, 10, 97, 98,  3,  5,  7,  8])
print(third_element)  # Output: 2

Slicing

# Slice behaves like NumPy arrays
sliced_vec = vec[1:3]
print(sliced_vec)  # Output: [10  97]

vec[2:5] = [51, 52, 53]
print(vec)            # Output: DynamicVector([ 1, 10, 51, 52, 53,  5,  7,  8])

vec[[1, 3, 5]] = [-1, -2, -3]
print(vec)            # Output: DynamicVector([ 1, -1, 51, -2, 53, -3,  7,  8])

Testing

This project uses pytest and pytest-xdist for testing. Tests are located in the tests folder. To run tests, install the required packages and execute the following command:

pip install pytest pytest-xdist

pytest  # run all tests, note options are set in the pyproject.toml file

 

Note, that the pyproject.toml file is configured to run pytest with the following arguments:

[tool.pytest.ini_options]
# agressive parallel options
addopts = "-ra --dist worksteal -nauto"

License

This project is licensed under the MIT License. See the LICENSE file for details.

Contributing

Contributions are welcome! Please open an issue or submit a pull request for any improvements or bug fixes.

Author

Scott E. Boyce