In order to convert between units of measure, we need to know what the conversion factors are. Unfortunately, different clients use different abbreviations to refer to the same units and that makes this information difficult to build into the system. We already have a system that can convert between equivalent units, but we need the ability to know which abbreviations refer to which units. To achieve this, we will add a column in Data Manager called Standard Unit that allows the data builder to specify which known unit corresponds to which abbreviation.
Multiple different abbreviations could map to the same unit.
- Millimeter
- Centimeter
- Meter
- Kilometer
- Inch
- Foot
- Yard
- Mile
- Sq. Millimeter
- Sq. Centimeter
- Sq. Meter
- Sq. Inch
- Sq. Foot
- Sq. Yard
- Acre
- Cu. Millimeter
- Cu. Centimeter
- Cu. Meter
- Milliliter
- Centiliter
- Liter
- Kiloliter
- Cu. Inch
- Cu. Foot
- Cu. Yard
- Board Foot
- Gallon
- Gram
- Kilogram
- Pound
- Ton -- if this is driven by a formula to represent a line item, the Standard unit will be FOOT.
The user will not be able to convert between any given unit using this system. For example, there is no known conversion between linear feet and the number of panels. That system would be complex because the user would have to specify conversion factors between every unit combination they wanted to support, would be prone to error, and be difficult to input.
Ultimately we feel that logic can be better supported in the quantity formula of a line item, and the units can be focused on the original purpose the user was trying to support which is to easily switch their estimate takeoff between metric and imperial units.
Metric Conversion
A new field will be added to line items that allow the user to select the alternate unit for that item. The alternate unit drop-down should only show units that are valid alternates. To be a valid alternate, the unit must be the same dimension as the primary unit but for the opposite system of measure. For example, if the primary unit is square feet (an imperial area), valid alternates are square meters, square centimeters, and square millimeters (metric areas); however, square yards (an imperial area) or cubic meters (a metric volume) would both be invalid. If the primary unit does not have a standard selected on the UoM page, then the Alternate Unit field should not be visible. The label for the Alternate unit should reflect the appropriate valid system of measure. IE if an imperial unit is selected as the primary, the label should read "Metric Unit", whereas if a metric unit is selected as primary, the label should read "Imperial Unit".
To update the Alternate units, you will export the database to Excel, in the line item tab, you will fill in the data in the Alternate Unit column and then reimport the spreadsheet.
Deleting a Unit
Deleting a unit will work in a similar way as modifying the UoM's standard unit definition. When deleting a unit, the user must select a replacement unit to update line items with. If the Line Item's primary unit is being updated and the alternate unit is still compatible, then it will be retained, otherwise, it will be cleared out. If the alternate unit is being updated and the replacement is compatible with the primary unit, then the chosen replacement will become the new alternate unit, otherwise, the line item's alternate will be cleared out.
Importing the Spreadsheet