Velocity Functions
The
velocity_functions table is designed to hold the velocity functions that specify the rate at which development occurs. A Development Project Proposal has a calculated variable called units_proposed that is the total number of units that will be built. The calculated variable annual_construction_schedule on the Development Project Proposal Components dataset uses units_proposed to select which of the velocity functions in this table should apply based on the building_type_id and units_proposed of the Development Project Proposal Component. The user can specify a record from this table, using the velocity_function_id, to specify the construction schedule for projects specified in the development_project_proposal base year table.
| Column Name |
Data Type |
Required |
Description |
| velocity_function_id |
Integer |
Y |
A unique identifier |
| annual_construction_schedule |
String |
Y |
A numbered list in brackets of the form, '[p1, p2,...,pn]', indicating with each entry the percentage complete of the project each year from its start. The last entry must be '100'. |
| building_type_id |
Integer |
Y |
The building type id for the velocity function |
| minimum_units |
Integer |
Y |
The minimum number of units for the velocity function |
| maximum_units |
Integer |
Y |
The maximum number of units for the velocity function |
A particular development_template_component or development_project_component will have one velocity_function_id attached to it. As an example, a velocity function with the annual construction schedule [0, 0, 0, 33, 66, 100] will have no construction in its first 3 years, will be 33% complete in year 4, and will be 66% and 100% complete in years 5 and 6, respectively.
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PeterMcNally - 11 Nov 2009