In some cases, you may want to create a new unit to track particular items (such as widgets, boxes, patients, etc.). Such a unit actually represents an amount of something. You could leave objects like these dimensionless, but for the purpose of viewing and plotting results, it may often be useful to assign units (e.g., 10 boxes instead of simply 10).
To do this, you can create a new dimensionless, as follows:
1. Create a new unit (e.g., widgets, with the abbreviation wdg)
2. When defining a value for the unit, define it as: 1 item.
3. Assign your new unit to the “Items” category.
Item is a built-in unit with no dimensions assigned to the “Items” category. The “Items” category also has several other built-in commonly required dimensionless units (pers for persons, kpers for thousands of persons, and Mpers for millions of persons).
You can repeat this process for other items (e.g., bolts, nuts, cars, etc.).
Warning: If you define two
“item units” like this, they can be added together and their resulting units
would be dimensionless. For example, if a bolt was defined as 1 item, and
a nut was defined as 1 item, you could add 100 bolts to 200 nuts, and express
the result in any dimensionless unit (e.g., pers).