Metadata-Version: 2.1
Name: linear-algebra-ulloa
Version: 0.0.1
Summary: Vector and matrix classes that can be used with each other.
Home-page: https://github.com/ulloaluis/linear-algebra
Author: Luis Ulloa
Author-email: ulloa@stanford.edu
License: UNKNOWN
Platform: UNKNOWN
Classifier: Programming Language :: Python :: 3
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Description-Content-Type: text/markdown

# linear-algebra
implemented vector and matrix classes with reST-formatted docstrings in Python 3+

## General Layout



The Vector class imitates the m x 1 vector from linear algebra and
contains many useful functions for dealing and interacting with Vectors.

Getting values directly from the vector should be done using the get(index)
function or [] operator since the comp vector location in memory may change with functions
like mag() or zero() (those which change current vector comp).

    class Vector

    __init__(comp)          - takes in a list of components or a valid mx1 Matrix

    resize(length)          - while preserving current elements or filling with 0's, changes current vector length

    set(comp, index=-1)     - sets entire list at once or one specific index/value

    get(index)              - returns item at specified index of vector

    zero()                  - turns the current vector into a zero vector and returns it

    mag()                   - returns the magnitude of current vector

    normalize(change=False) - returns normalized current vector, if change=True, internal vector is updated

    same_normalized(other)  - returns True/False depending on equality of the two vectors once normalized

    dot(other)              - returns the dot product of th two vectors

    cross(other)            - returns the cross product of u x v (u is current vector, v is other)

    perp(other)             - returns True/False if current and other are/aren't perpendicular

    parallel(other)         - returns True/False if current and other are/aren't parallel

    indep(other)          - returns True/False if curr vector and other vector(s) are linearly independent

    operator +              - returns sum of two vectors, component wise addition

    operator -              - returns difference of two vectors, component wise subtraction

    operator *              - alternate for dot product, or can use for vector scaling

    operator **             - returns original vector with its components raised to power

    operator ==             - checks to see if lists are equal

    to string method        - format: "<elem1, elem2, ...>"

    len() method            - can use len() to get vector length

    get and set []          - user can get and set values in vector with index based operations []


    comp = vector composition, list of components

    length = number of components in vector

    rows = same as length, used with cols for backwards compatibility with Matrix

    cols = 1 (num of columns)


The Matrix class imitates the matrix concept from linear algebra and allows
for different ways of dealing and interacting with matrices and vectors.

Getting values directly from the vector should be done using the get(row, col)
function or [], [][] operator since the matrix comp location in memory may change with functions
that change the underlying data type.

    class Matrix

    __init__(comp)          - takes in a list of components or a valid Vector

    resize(rows, cols)      - while preserving current elements or filling with 0's, changes current vector length

    set(comp, index=None)   - sets entire list at once or one specific index/value (tuple or array as (row, col))

    get(row=None,col=None)  - can get a specific row, column, or entire matrix composition (no args for matrix)

    zero()                  - replaces values in current matrix with all zeroes and returns it

    det()                   - takes the determinant of the current NxN matrix

    transpose()             - transposes the current mxn matrix to an nxm matrix (1st row becomes 1st col, etc.)

    row_echelon()           - returns the current matrix in row echelon form

    row_reduce()            - returns the current matrix to reduced row echelon form

    identity(n)             - static method that returns the nxn identity matrix

    combine(first, second)  - static method that combines two matrices by concatenation

    inverse()               - returns the inverse of current nxn matrix, or None if singular

    operator +              - returns sum of two matrices, component wise addition

    operator -              - returns difference of two matrices, component wise subtraction

    operator *              - matrix multiplication, matrix-vector product, scalar multiplication

    operator **             - returns original matrix with its components raised to power

    operator ==             - checks to see if internal lists are equal

    to string method        - format: "[row1\n row2\n row3\n ...]" and floats are shown as fractions

    len() method            - returns tuple formatted as (row, col)

    get and set [][]        - can get rows and specific values with [] or [][], and set specific values with [][]


    comp = matrix composition, list of lists where each list is a row

    rows = number of rows in matrix

    cols = number of columns in matrix

## Tests

There is a file for writing tests. At the moment, it is only a series of assertions. In the future, I will update the testing file to use a more standardized version/library for testing.

## Docstrings/Documentation

There is thorough documentation throughout the library. Python library contains a help() function that could be used to view the docstrings for a specific class/method.

Class: help(classname)

Method: help(classname.methodname)

For example, help(Vector.resize) shows you ...

    resize(self, length)

        Re-sizes the vector to the specified length. If length is greater than

        current size, the new components are initialized with 0, otherwise if length

        is less than current size, the last few components are lost.

        :param length: new length of vector

        :type length: int

        :return: current vector, now resized

        :rtype: Vector

and vice versa. help(Vector) and help(Matrix) return major class overviews.

## Using library

Import the linear module into your library. The exact file with all of the necessary code is linear.py.

## Potential additions to library in future

### Vector Class

* ~~Method for checking if current vector and other vector are orthogonal~~

* Support for plotting/graphing a certain amount of 2D maybe 3D vectors using matplotlib or a similar library

* ~~Cross products~~

### Matrix Class

* ~~Determinant~~

* ~~Row Reducing Matrices~~

* ~~Finding inverse of Matrices~~

* ~~Transposing matrices~~

* Standalone function for fitting a straight line with least squares approximation

* General least squares method as part of matrices class

### Additional

* ~~index access with [] [][] operator~~

* ~~identify whether a set of vectors are linearly independent~~

* ~~identify whether two vectors are parallel~~

* ~~static method for generating arbitrarily sized identity matrix~~

* ~~static method for concatenating two matrices~~

* ~~floats are shown as proper fractions when printed~~

* ~~equality tests account for floating point error~~







