linear-transforms 0.0.1

Python coordinate frame transform library

Transforms: Python coordinate frame transform library

Library to ease work with 3D coordinate frame transformations, by two means:

• Easy-to-operate-with symbolic/numerical linear transformation classes
• LaTeX export and enhanced console printing of transformation matrices

Nice experiment to learn about operator overloading.

Antonio Lopez Rivera, 2020

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1. Install

2. Usage and Syntax

3. To-do

1. Install

1. Place transforms.py and utilities.py in your root directory (or another, but mind the import)
2. from transforms import Tx, Ty, Tz

2. Usage and Syntax

All code available in demo.py.

2.1 Creating a Linear Transformation

Transformation describing the position of a rotated object (by angle a) from its original frame of reference:

Ta = Tx(a)

The linear transformation class may be initialized with a Sympy.Symbol, or regular values for the rotation angle

2.2 Lambdifying a symbolic linear transformation

Turning a symbolic linear transformation to a numerical one can be done by calling the transformation itself.

T_num = Ta(<VALUE>)

2.3 Operating with Linear Transformations

Transform concatenation is defined with the multiplication sign, as well as the addition sign. The multiplication notation is recommended.

Tt = Ta*Tb*Tc
TT = Ta+Tb+Tc

Tt == TT

Transform multiplication with NumPy or SymPy arrays is defined with the multiplication sign alone.

r = np.array([1, 1, 1])

r_tr = Tt*r

2.4 Inspecting matrices

LaTeX

Transformations, symbolic and numerical, can be outputed to LaTeX with the function call below. The latex equation will be visible in the terminal in light blue.

r_tr.to_latex()

Printing

Printing a transformation will output an ASCII representation in the terminal

print(r_tr)

3. To-do

1. n-dimensional transform matrix generation