Expression Syntax
Reference for the quantity expression field in assembly components.
Expression Syntax
Quantity expressions are what you type into a component’s Quantity field when building an assembly. They tell the system how much of this product is needed per output unit.
Constants
Plain numbers work. The unit is implied by the product’s base UOM.
| Expression | Meaning |
|---|---|
0.15 | 0.15 units of the product per assembly output unit |
12 | 12 units |
0.05 | 0.05 hours of labour per output unit |
Variables
Reference a variable by wrapping its name in { }. Type { in the field to open the variable picker.
| Expression | Meaning |
|---|---|
{thickness} | Use the value of the thickness variable |
{coats} | Use the value of the coats variable |
{waste_factor} | Use the value of the waste_factor variable |
Arithmetic
Combine constants and variables with the standard operators +, -, *, /, and parentheses.
| Expression | Meaning |
|---|---|
0.15 * (1 + {waste_factor}) | Material with waste added in |
{thickness} * {density} | Two variables multiplied (e.g. for mass calculations) |
0.05 * {coats} | Labour scaled by coat count |
12 / {coverage_rate} | Constant divided by a variable |
Tips
- Prefer expressions over inflated constants.
0.15 * (1 + {waste_factor})is clearer than0.165and lets the user adjust waste at apply-time. - Use system variables where they exist (
thickness,waste_factor,coverage_rate, etc.) so other estimators recognise the input. - Names matter for picker UX — see Tips and pitfalls.