BIASDISTCARTESIAN
The BIASDISTCARTESIAN
field operator works in a similar way to the BIAS
field operator. It allows you to bias the score of results at query time according to the proximity of the specified field to a particular location, specified using Cartesian coordinates.
TIP: If your document location fields contain regions (in Well-known text POLYGON format), the BIASDISTCARTESIAN
operator calculates distances from the geometric center of the region.
Specify BIASDISTCARTESIAN
in the format:
FieldText=BIASDISTCARTESIAN{coordX,coordY,range,percentage}:POSITION
where:
coordX
|
is the X coordinate. |
coordY
|
is the Y coordinate. |
range
|
is the distance in kilometers from the coordinates. If the fields contain the coordinates of a location that is within this distance of the coordinates, the results weight increases or decreases according to the specified percentage. |
percentage
|
is a percentage in the range –100 to 100. If the value of the field is within the specified range, the score of the result increases or decreases according to how close the value is to the optimum. |
POSITION
|
The document field or fields that contain the location value. You can use one of the following options to specify location fields:
|
For example:
FieldText=BIASDISTCARTESIAN{10,11,5,7}:X:Y
FieldText=BIASDISTCARTESIAN{10,11,5,7}:POSITION
In these examples, all documents whose (X/Y) position is within a distance of 5 units of the point (10,11
) are given a relevance boost. The maximum boost of 7
percent is given to documents at the given point. The boost decreases linearly down to 0 boost at 5 units.
In the first example, the location data is stored in two document fields, X
and Y
. In the second example, the location data is stored in a single POSITION
field.