Filter Function Reference

This reference describes all filter functions that can be used in WFS/WMS filtering or in SLD expressions.

The list of functions available on a Geoserver instance can be determined by browsing to http://localhost:8080/geoserver/wfs?request=GetCapabilities and searching for ogc:FunctionNames in the returned XML. If a function is described in the Capabilities document but is not in this reference, then it might mean that the function cannot be used for filtering, or that it is new and has not been documented. Ask for details on the user mailing list.

Unless otherwise specified, none of the filter functions in this reference are understood natively by the data stores, and thus expressions using them will be evaluated in-memory.

Function argument type reference

Type Description
Double Floating point number, 8 bytes, IEEE 754. Ranges from 4.94065645841246544e-324d to 1.79769313486231570e+308d
Float Floating point number, 4 bytes, IEEE 754. Ranges from 1.40129846432481707e-45 to 3.40282346638528860e+38. Smaller range and less accurate than Double.
Integer Integer number, ranging from -2,147,483,648 to 2,147,483,647
Long Integer number, ranging from -9,223,372,036,854,775,808 to +9,223,372,036,854,775,807
Number A numeric value of any type
Object A value of any type
String A sequence of characters
Timestamp Date and time information

Comparison functions

Name Arguments Description
between num:Number, low:Number, high:Number returns true if low <= num <= high
equalTo a:Object, b:Object Can be used to compare for equality two numbers, two strings, two dates, and so on
greaterEqualThan x:Object, y:Object Returns true if x >= y. Parameters can be either numbers or strings (in the second case lexicographic ordering is used)
greaterThan x:Object, y:Object Returns true if x > y. Parameters can be either numbers or strings (in the second case lexicographic ordering is used)
in2, in3, in4, in5, in6, in7, in8, in9, in10 candidate:Object, v1:Object, ..., v9:Object Returns true if candidate is equal to one of the v1, ..., v9 values. Use the function name matching the number of arguments specified.
isLike string:String, pattern:String Returns true if the string matches the specified pattern. For the full syntax of the pattern specification see the Java Pattern class javadocs
isNull obj:Object Returns true the passed parameter is null, false otherwise
lessThan x:Object, y:Object Returns true if x < y. Parameters can be either numbers or strings (in the second case lexicographic ordering is used
lessEqualThan x:Object, y:Object Returns true if x <= y. Parameters can be either numbers or strings (in the second case lexicographic ordering is used
not bool:Boolean Returns the negation of bool
notEqual x:Object, y:Object Returns true if x and y are equal, false otherwise

Control functions

Name Arguments Description
if_then_else condition:Boolean, x:Object, y: Object Returns x if the condition is true, y otherwise

Environment function

This function returns the value of environment variables defined in various contexts. Contexts which define environment variables include SLD rendering and the WMS Animator.

Name Arguments Description
env variable:String Returns the value of the environment variable variable.

Feature functions

Name Arguments Description
id feature:Feature returns the identifier of the feature
PropertyExists f:Feature, propertyName:String Returns true if f has a property named propertyName
property f:Feature, propertyName:String Returns the value of the property propertyName. Allows property names to be computed or specified by Variable substitution in SLD.

Spatial Relationship functions

For more information about the precise meaning of the spatial relationships consult the OGC Simple Feature Specification for SQL

Name Arguments Description
contains a:Geometry, b:Geometry Returns true if the geometry a contains b
crosses a:Geometry, b:Geometry Returns true if a crosses b
disjoint a:Geometry, b:Geometry Returns true if the two geometries are disjoint, false otherwise
equalsExact a:Geometry, b:Geometry Returns true if the two geometries are exactly equal, same coordinates in the same order
equalsExactTolerance a:Geometry, b:Geometry, tol:Double Returns true if the two geometries are exactly equal, same coordinates in the same order, allowing for a tol distance in the corresponding points
intersects a:Geometry, b:Geometry Returns true if a intersects b
isWithinDistance a: Geometry, b:Geometry, distance: Double Returns true if the distance between a and b is less than distance (measured as an euclidean distance)
overlaps a: Geometry, b:Geometry Returns true a overlaps with b
relate a: Geometry, b:Geometry Returns the DE-9IM intersection matrix for a and b
relatePattern a: Geometry, b:Geometry, pattern:String Returns true if the DE-9IM intersection matrix for a and b matches the specified pattern
touches a: Geometry, b: Geometry Returns true if a touches b according to the SQL simple feature specification rules
within a: Geometry, b:Geometry Returns true is fully contained inside b

Geometric functions

Name Arguments Description
area geometry:Geometry The area of the specified geometry. Works in a Cartesian plane, the result will be in the same unit of measure as the geometry coordinates (which also means the results won’t make any sense for geographic data)
boundary geometry:Geometry Returns the boundary of a geometry
boundaryDimension geometry:Geometry Returns the number of dimensions of the geometry boundary
buffer geometry:Geometry, distance:Double Returns the buffered area around the geometry using the specified distance
bufferWithSegments geometry:Geometry, distance:Double, segments:Integer Returns the buffered area around the geometry using the specified distance and using the specified number of segments to represent a quadrant of a circle.
centroid geometry:Geometry Returns the centroid of the geometry. Can be often used as a label point for polygons, though there is no guarantee it will actually lie inside the geometry
convexHull geometry:Geometry Returns the convex hull of the specified geometry
difference a:Geometry, b:Geometry Returns all the points that sit in a but not in b
dimension a:Geometry Returns the dimension of the specified geometry
distance a:Geometry, b:Geometry Returns the euclidean distance between the two geometries
endAngle line:LineString Returns the angle of the end segment of the linestring
endPoint line:LineString Returns the end point of the linestring
envelope geometry:geometry Returns the polygon representing the envelope of the geometry, that is, the minimum rectangle with sides parallels to the axis containing it
exteriorRing poly:Polygon Returns the exterior ring of the specified polygon
geometryType geometry:Geometry Returns the type of the geometry as a string. May be Point, MultiPoint, LineString, LinearRing, MultiLineString, Polygon, MultiPolygon, GeometryCollection
geomFromWKT wkt:String Returns the Geometry represented in the Well Known Text format contained in the wkt parameter
geomLength geometry:Geometry Returns the length/perimeter of this geometry (computed in Cartesian space)
getGeometryN collection:GeometryCollection, n:Integer Returns the n-th geometry inside the collection
getX p:Point Returns the x ordinate of p
getY p:Point Returns the y ordinate of p
getZ p:Point Returns the z ordinate of p
interiorPoint geometry:Geometry Returns a point that is either interior to the geometry, when possible, or sitting on its boundary, otherwise
interiorRingN polyg:Polygon, n:Integer Returns the n-th interior ring of the polygon
intersection a:Geometry, b:Geometry Returns the intersection between a and b. The intersection result can be anything including a geometry collection of heterogeneous, if the result is empty, it will be represented by an empty collection.
isClosed line: LineString Returns true if line forms a closed ring, that is, if the first and last coordinates are equal
isEmpty geometry:Geometry Returns true if the geometry does not contain any point (typical case, an empty geometry collection)
isometric geometry:Geometry, extrusion:Double Returns a MultiPolygon containing the isometric extrusions of all components of the input geometry. The extrusion distance is extrusion, expressed in the same unit as the geometry coordinates. Can be used to get a pseudo-3d effect in a map
isRing line:LineString Returns true if the line is actually a closed ring (equivalent to isRing(line) and isSimple(line))
isSimple line:LineString Returns true if the geometry self intersects only at boundary points
isValid geometry: Geometry Returns true if the geometry is topologically valid (rings are closed, holes are inside the hull, and so on)
numGeometries collection: GeometryCollection Returns the number of geometries contained in the geometry collection
numInteriorRing poly: Polygon Returns the number of interior rings (holes) inside the specified polygon
numPoint geometry: Geometry Returns the number of points (vertexes) contained in geometry
offset geometry: Geometry, offsetX:Double, offsetY:Double Offsets all points in a geometry by the specified X and Y offsets. Offsets are working in the same coordinate system as the geometry own coordinates.
pointN geometry: Geometry, n:Integer Returns the n-th point inside the specified geometry
startAngle line: LineString Returns the angle of the starting segment of the input linestring
startPoint line: LineString Returns the starting point of the input linestring
symDifference a: Geometry, b:Geometry Returns the symmetrical difference between a and b (all points that are inside a or b, but not both)
toWKT geometry: Geometry Returns the WKT representation of geometry
union a: Geometry, b:Geometry Returns the union of a and b (the result may be a geometry collection)
vertices geom: Geometry Returns a multi-point made with all the vertices of geom

Math functions

Name Arguments Description
abs value:Integer The absolute value of the specified Integer value
abs_2 value:Long The absolute value of the specified Long value
abs_3 value:Float The absolute value of the specified Float value
abs_4 value:Double The absolute value of the specified Double value
acos angle:Double Returns the arc cosine of an angle in radians, in the range of 0.0 through PI
asin angle:Double Returns the arc sine of an angle in radians, in the range of -PI / 2 through PI / 2
atan angle:Double Returns the arc tangent of an angle in radians, in the range of -PI/2 through PI/2
atan2 x:Double, y:Double Converts a rectangular coordinate (x, y) to polar (r, theta) and returns theta.
ceil x: Double Returns the smallest (closest to negative infinity) double value that is greater than or equal to x and is equal to a mathematical integer.
cos angle: Double Returns the cosine of an angle expressed in radians
double2bool x: Double Returns true if x is zero, false otherwise
exp x: Double Returns Euler’s number e raised to the power of x
floor x: Double Returns the largest (closest to positive infinity) value that is less than or equal to x and is equal to a mathematical integer
IEEERemainder x: Double, y:Double Computes the remainder of x divided by y as prescribed by the IEEE 754 standard
int2bbool x: Integer Returns true if x is zero, false otherwise
int2ddouble x: Integer Converts x to a Double
log x: Integer Returns the natural logarithm (base e) of x
max, max_3, max_4 x1: Double, x2:Double, x3:Double, x4:Double Returns the maximum between x1, ..., x4
min, min_3, min_4 x1: Double, x2:Double, x3:Double, x4:Double Returns the minimum between x1, ..., x4
pi None Returns an approximation of pi, the ratio of the circumference of a circle to its diameter
pow base:Double, exponent:Double Returns the value of base raised to the power of exponent
random None Returns a Double value with a positive sign, greater than or equal to 0.0 and less than 1.0. Returned values are chosen pseudo-randomly with (approximately) uniform distribution from that range.
rint x:Double Returns the Double value that is closest in value to the argument and is equal to a mathematical integer. If two double values that are mathematical integers are equally close, the result is the integer value that is even.
round_2 x:Double Same as round, but returns a Long
round x:Double Returns the closest Integer to x. The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type Integer. In other words, the result is equal to the value of the expression (int)floor(a + 0.5)
roundDouble x:Double Returns the closest Long to x
tan angle:Double Returns the trigonometric tangent of angle
toDegrees angle:Double Converts an angle expressed in radians into degrees
toRadians angle:Double Converts an angle expressed in radians into degrees

String functions

String functions generally will accept any type of value for String arguments. Non-string values will be converted into a string representation automatically.

Name Arguments Description
Concatenate s1:String, s2:String, ... Concatenates any number of strings. Non-string arguments are allowed.
strCapitalize sentence:String Fully capitalizes the sentence. For example, “HoW aRe YOU?” will be turned into “How Are You?”
strConcat a:String, b:String Concatenates the two strings into one
strEndsWith string:String, suffix:String Returns true if string ends with suffix
strEqualsIgnoreCase a:String, b:String Returns true if the two strings are equal ignoring case considerations
strIndexOf string:String, substring:String Returns the index within this string of the first occurrence of the specified substring, or -1 if not found
strLastIndexOf string:String, substring:String Returns the index within this string of the last occurrence of the specified substring, or -1 if not found
strLength string:String Returns the string length
strMatches string:String, pattern:String Returns true if the string matches the specified regular expression. For the full syntax of the pattern specification see the Java Pattern class javadocs
strReplace string:String, pattern:String, replacement:String, global: boolean Returns the string with the pattern replaced with the given replacement text. If the global argument is true then all occurrences of the pattern will be replaced, otherwise only the first. For the full syntax of the pattern specification see the Java Pattern class javadocs
strStartsWith string:String, prefix:String Returns true if string starts with prefix
strSubstring string:String, begin:Integer, end:Integer Returns a new string that is a substring of this string. The substring begins at the specified begin and extends to the character at index endIndex - 1 (indexes are zero-based).
strSubstringStart string:String, begin:Integer Returns a new string that is a substring of this string. The substring begins at the specified begin and extends to the last character of the string
strToLowerCase string:String Returns the lower case version of the string
strToUpperCase string:String Returns the upper case version of the string
strTrim string:String Returns a copy of the string, with leading and trailing white space omitted

Parsing and formatting functions

Name Arguments Description
dateFormat date:Timestamp, format:String Formats the specified date according to the provided format. The format syntax can be found in the Java SimpleDateFormat javadocs
dateParse dateString:String, format:String Parses a date from a dateString formatted according to the format specification. The format syntax can be found in the Java SimpleDateFormat javadocs
numberFormat number:Double, format:String Formats the number according to the specified format. The format syntax can be found in the Java DecimalFormat javadocs
parseBoolean boolean:String Parses a string into a boolean. The empty string, f, 0.0 and 0 are considered false, everything else is considered true.
parseDouble number:String Parses a string into a double. The number can be expressed in normal or scientific form.
parseInt number:String Parses a string into an integer.
parseLong number:String Parses a string into a long integer

Transformation functions

Transformation functions transform values from one data space into another. These functions provide a concise way to compute styling parameters from feature attribute values. See also Styling using Transformation Functions.

Name Arguments Description
Recode

lookupValue:Object,

data:Object, value:Object, ...

Transforms a lookupValue from a set of discrete data values into another set of values. Any number of data/value pairs may be specified.
Categorize

lookupValue:Object, value:Object,

threshold:Object, ... value:Object,

belongsTo : String

Transforms a continuous-valued attribute value into a set of discrete values. lookupValue and value must be an orderable type (typically numeric). The initial value is required. Any number of additional threshold/value pairs may be specified. belongsTo is optional, with the value succeeding or preceding. It defines which interval to use when the lookup value equals a threshold value.
Interpolate

lookupValue:Numeric,

data:Numeric, value:Numeric or #RRGGBB, ...

mode:String, method:String

Transforms a continuous-valued attribute value into another continuous range of values. Any number of data/value pairs may be specified. mode is optional, with the value linear, cosine or cubic. It defines the interpolation algorithm to use. method is optional, with the value numeric or color. It defines whether the target values are numeric or RGB color specifications.
Next: Styling