stubbing out gravity model

2016-06-03 10:36:21 -04:00
parent 21dd956c15
commit 4782d39849
4 changed files with 125 additions and 0 deletions
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+## Gravity Model 
+
+### CDB_Gravity()
+
+The Gravity Model is derived from newtons law of gravity and is used to estimate the degree of interaction between two places 
+
+#### Arguments 
+
+| Name | Type | Description | 
+|------|------|-------------|
+| t_id     | bigint[]    |     |
+| t_geom   | geometry[]  |     |
+| t_weight | numeric[]   |     |
+| s_id     | bigint[]    |     |
+| s_geom   | geometry[]  |     |
+| s_pop    | numeric[]   |     |
+| target   | bigint      |     |
+| radius   | integer     |     |
+| minval   | numeric     |     |
+
+
+#### Returns 
+
+| Column Name | Type | Description |
+|-------------|------|-------------|
+| the_geom  | Numeric | |
+| source_id | bigint  | |
+| target_id | bigint  | |
+| dist      | Numeric | |
+| n         | Numeric | |
+| hpop      | NUMERIC | |
+
+
+#### Example Usage
+
+```sql
+SELECT CDB_GRAVITY ();
+```
+
+