Note some inputs will generate negative tube lengths. One possible upgrade would involve pruning the bracket combinations that generate non-physical results from the list. Results are rouned to three decimal places, so it may be a good idea to use cm or in instead of meters or feet
The constants are editable, but still called constants because they aren't expected to be changed very often, and they come with default values.
The calculated values are between tube intersections, so a tube may need to be longer or shorter in practice.