isT

by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - Kinematics and Frames
Introduced first in SolidGeometry 5.2, Creation date: 2022-11-04, Last change: 2025-09-15

returns whether a variable is a HT matrix or a list of HT matrices



See Also: isSG , mat2celldim3 , cell2matdim3

Example Illustration

missing image of isT(T)

Syntax

ii=isT(T)

Input Parameter

T: 3x3 or 4x4 HT frame or array or cell list

Output Parameter

ii: result true or false

Examples


isT(eye(3))
isT(eye(4))
TL=TofPLpath(PLcircle)
isT(TL)
isT(mat2celldim3(TL))
isT(rot([3,3,3]))



Copyright 2022-2025 Tim C. Lueth. All rights reserved. The code is the property of Tim C. Lueth and may not be redistributed or modified without explicit written permission. This software may be used free of charge for academic research and teaching purposes only. Commercial use, redistribution, modification, or reverse engineering is strictly prohibited. Access to source code is restricted and granted only under specific agreements. For licensing inquiries or commercial use, please contact: Tim C. Lueth

Algorithm (Workflow)

This function, isT, determines whether a given variable T is a homogeneous transformation (HT) matrix or a list of HT matrices. The function is part of the SolidGeometry library and was introduced in version 5.2.

Input Parameters

Output Results

Algorithm Steps

  1. Check if T is a 3x3 matrix and its third row is [0 0 1]. If true, set ii to true.
  2. Check if T is a 4x4 matrix and its fourth row is [0 0 0 1]. If true, set ii to true.
  3. If T is a 3D array with more than one matrix along the third dimension, iterate through each matrix and recursively check if each is an HT matrix. Set ii to true only if all matrices are HT matrices.
  4. If T is a cell array, iterate through each cell and recursively check if each element is an HT matrix. Set ii to true only if all elements are HT matrices.
  5. If none of the above conditions are met, set ii to false.

Additional Functionality

If the function is called without output arguments and ii is true, it will call SGfigure and tplot to visualize the transformation.

Algorithm explaination created using ChatGPT on 2025-08-18 23:53. (Please note: No guarantee for the correctness of this explanation)

Last html export of this page out of FM database by TL: 2025-09-21