PRETTY_NAME="Ubuntu 24.04.5 LTS"
NAME="Ubuntu"
VERSION_ID="24.04"
VERSION="24.04.5 LTS (Noble Numbat)"
VERSION_CODENAME=noble
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=noble
LOGO=ubuntu-logo
aarch64
Python 3.12.3
python3-numpy	1:1.26.4+ds-6ubuntu1
python3-yaml	6.0.1-2build2
ros-jazzy-fastrtps	2.14.6-1noble.20260902.013353
ros-jazzy-geometry-msgs	5.3.8-1noble.20260902.122255
ros-jazzy-nav-msgs	5.3.8-1noble.20260902.123754
ros-jazzy-rclpy	7.1.12-1noble.20260902.143245
ros-jazzy-rmw-fastrtps-cpp	8.4.4-1noble.20260902.140744
ros-jazzy-tf2-geometry-msgs	0.36.22-1noble.20260902.170215
ros-jazzy-tf2-py	0.36.22-1noble.20260902.150411
ros-jazzy-tf2-ros-py	0.36.22-1noble.20260902.150658

Validation date: 2026-10-12
Image: docker.io/library/ros:jazzy-ros-base
Pinned image: ros:jazzy-ros-base@sha256:066420e07f60aa18262f2479981def87ebcfcec42eefb0c0c57c4a46098348ca
Image OS/architecture: linux/arm64
Host: macOS ARM64, Docker Desktop
Network: none (three nodes in one process inside a disposable container)
Read-only mount: exercise directory -> /lesson
ROS_DOMAIN_ID=72
RMW_IMPLEMENTATION=rmw_fastrtps_cpp

Three script runs passed with identical output after the received buffer-tree
and composed-transform checks were added. A fourth run also passed after all
scalar comparisons were tightened to an absolute 1e-9 tolerance (rel_tol=0).
sample-output.txt matches this output. The last two runs used the exact
Docker arguments printed in the article, including the /lesson mount. The script
keeps ROS callbacks running while waiting for subscription discovery and message
delivery; each wait has a ten-second
wall-clock deadline. These waits are not measurements of transport latency.

The test uses exact synthetic pose samples stamped 10 and 12, queries at 11,
and deliberate failure queries at 9 and 13. It publishes no /clock and does not
use the host's current time as a data timestamp. No wheel odometry, SLAM,
localization accuracy, hardware behavior, or network performance is measured.
No dependency installation was needed; all packages were present in the image.
Each verification container was removed automatically by Docker --rm.