Units
Units in Granta MI define the unit of measurement in which numeric data is stored in the database.
Database units may be defined as:
- Base units, for example metre, kilogram, mole, second, strain, Ampere, Temperature (Kelvin/Celsius). These are units which are not derived from any other units.
- Units that are a multiple of another unit, for example,
inch=
0.0254*[m], foot=12*[in], angstrom=1e-010*[m], minute=60*[s] - Derived units that are defined in terms of other units via an equation, for example:
- Watt is defined as:
[J]/[s] - pascal is defined as:
[N]/([m]^2) - % strain/°C is defined as:
[%strain]/[K] - BTU/hr.ft.°F is defined as:
[BTU]*[ft]/([hr]*[ft]^2*[°R])
- Watt is defined as:
Unit conversion equations can include numbers, unit symbols enclosed in square brackets [ ], parentheses for nesting, and the operators / (divide by), * (multiply by), and ^ (raise to the power of).
Attributes, Meta-attributes, Parameters, Constants, and Expressions can all have units. All numeric data is stored in the database unit assigned to the Attribute but data can be displayed in units other than the database unit via a Unit System which converts the underlying data value into the equivalent value with a different unit.