Molecule/molecule.boilerplate/molecule.boilerplate.api/Keywords

Keywords

molecule.boilerplate.api.Keywords

See theKeywords companion trait

object Keywords extends KeywordsStable

Attributes

Companion: trait
Source: Keywords.scala
Graph
Supertypes: trait KeywordsStable

class Object

trait Matchable

class Any
Self type: Keywords.type

Members list

Grouped members

aggrNumber

Average of attribute values.

Apply avg keyword to attribute to return average of attribute values of entities matching the molecule.

for {
 _ <- Match.sKeywords.insert(1, 2, 4)
 _ <- Match.score(avg).get.map(_.head ==> 2.3333333333333335) // (1 + 2 + 4) / 3
} yield ()

Attributes

Returns: Double
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object avg

Median of attribute values.

Apply median keyword to attribute to return median of attribute values of entities matching the molecule.

for {
 _ <- Match.sKeywords.insert(1, 2, 4)
 _ <- Match.score(median).get.map(_.head ==> 2)
} yield ()

OBS: When it comes to an even number of values, Datomic has a special implementation of median that is different from the one described on the Wiki entry on the median function.

Datomic calculates the median of even number of values as the average of the two middle numbers rounded down to nearest whole number

for {
 _ <- Match.sKeywords.insert(1, 2, 3, 4)
 _ <- Match.score(median).get.map(_.head ==> 2) // (2 + 3) / 2 = 2.5 rounded down to 2
} yield ()

With decimal numbers this can go wrong:

for {
 _ <- Match.sKeywords.insert(1.0, 2.5, 2.5, 3.0)
 _ <- Match.score(median).get.map(_.head ==> 2) // (2.5 + 2.5) / 2 = 2.5 rounded down to 2 (This is wrong and bug report has been filed)
} yield ()

Attributes

Returns: Value of Attribute type
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object median

Variance of attribute values.

Apply stddev keyword to attribute to return variance of attribute values of entities matching the molecule.

for {
 _ <- Match.sKeywords.insert(1, 2, 4)
 _ <- Match.score(stddev).get.map(_.head ==> 1.247219128924647)
} yield ()

Attributes

Returns: Double
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object stddev

Sum of attribute values.

Apply sum keyword to attribute to return sum of attribute values of entities matching the molecule.

for {
 _ <- Match.sKeywords.insert(1, 2, 4)
 _ <- Match.score(sum).get.map(_.head ==> 7)
} yield ()

Attributes

Returns: Value of Attribute type
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object sum

Variance of attribute values.

Apply variance keyword to attribute to return variance of attribute values of entities matching the molecule.

for {
 _ <- Match.sKeywords.insert(1, 2, 4)
 _ <- Match.score(variance).get.map(_.head ==> 1.5555555555555556)
} yield ()

Attributes

Returns: Double
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object variance

aggregates

Count of attribute values.

Apply count keyword to attribute to return count of attribute values of entities matching the molecule.

for {
 _ <- Person.firstName.lastName.age insert List(
   ("Ben", "Hayday", 42),
   ("Liz", "Taylor", 34),
   ("Liz", "Swifty", 34),
   ("Liz", "Mooray", 25)
 )
 _ <- Person.firstName.age(count).get.map(_ ==> List(
   ("Ben", 1),
   ("Liz", 3) // 34, 34, 25
 ))
} yield ()

Attributes

Returns: Int
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrInt

trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object count

Count of distinct attribute values.

Apply countDistinct keyword to attribute to return count of distinct attribute values of entities matching the molecule.

for {
 _ <- Person.firstName.lastName.age insert List(
   ("Ben", "Hayday", 42),
   ("Liz", "Taylor", 34),
   ("Liz", "Swifty", 34),
   ("Liz", "Mooray", 25)
 )
 _ <- Person.firstName.age(countDistinct).get.map(_ ==> List(
   ("Ben", 1),
   ("Liz", 2) // 34, 25
 ))
} yield ()

Attributes

Returns: Int
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrCoalesce

trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Show all
Known subtypes: object countDistinct

Distinct attribute values.

Apply distinct keyword to attribute to return Vector of distinct attribute values of entities matching the molecule.

for {
 _ <- Person.firstName.lastName.age insert List(
   ("Ben", "Hayday", 42),
   ("Liz", "Taylor", 34),
   ("Liz", "Swifty", 34),
   ("Liz", "Mooray", 25)
 )
 _ <- Person.firstName.age(distinct) insert List(
   ("Ben", 42),
   ("Liz", Vector(34, 25)) // only single 34 returned
 )
} yield ()

Attributes

Returns: List[attribute-type]
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: object distinct

Maximum attribute value(s).

Apply max keyword to attribute to return the maximum attribute value of entities matching the molecule.

for {
 _ <- Person.age.insert(25, 34, 37, 42, 70)
 _ <- Person.age(max).get.map(_.head ==> 70)
} yield ()

Apply max(n) to return Vector of the n biggest values.

Person.age(max(3)).get.map(_.head ==> Vector(37, 42, 70))

Attributes

Note: max/max(n) supports all value types (via comparators).
max(n) Can at most return the number of values that match.
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: object max

Minimum attribute value(s).

Apply min keyword to attribute to return the minimum attribute value of entities matching the molecule.

for {
 _ <- Person.age.insert(25, 34, 37, 42, 70)
 _ <- Person.age(min).get.map(_.head ==> 25)
} yield ()

Apply min(n) to return Vector of the n smallest values.

Person.age(min(3)).get.map(_.head ==> Vector(25, 34, 37))

Attributes

Note: min/min(n) supports all value types (via comparators).
min(n) Can at most return the number of values that match.
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: object min

Sample attribute value(s).

Apply sample keyword to attribute to return a single sample (random) attribute value of entities matching the molecule.

for {
 _ <- Person.age.insert(25, 34, 37, 42, 70)
 _ <- Person.age(sample).get.map(_.head ==> 42) // or other..
} yield ()

Apply sample(n) to return Vector of up to n distinct sample values.

Person.age(sample(3)).get.map(_.head ==> Vector(70, 25, 37)) // or other..

Attributes

Note: Can at most return the number of values that match.
Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: object sample

Type members

Inherited classlikes

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: trait avg

object avg

trait count

object count

trait countDistinct

object countDistinct

trait median

object median

trait stddev

object stddev

trait sum

object sum

trait variance

object variance
Show all

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait AggrKw

trait Kw

class Object

trait Matchable

class Any
Known subtypes: trait count

object count

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait Kw

class Object

trait Matchable

class Any
Known subtypes: trait AggrCoalesce

trait avg

object avg

trait count

object count

trait countDistinct

object countDistinct

trait median

object median

trait stddev

object stddev

trait sum

object sum

trait variance

object variance

trait AggrInt

trait distinct

object distinct

trait max

object max

trait min

object min

trait sample

object sample
Show all

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: class Object

trait Matchable

class Any
Known subtypes: trait AggrKw

trait AggrCoalesce

trait avg

object avg

trait count

object count

trait countDistinct

object countDistinct

trait median

object median

trait stddev

object stddev

trait sum

object sum

trait variance

object variance

trait AggrInt

trait distinct

object distinct

trait max

object max

trait min

object min

trait sample

object sample

class maxs

class mins

class samples
Show all

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait Serializable

trait Product

trait Equals

trait Kw

class Object

trait Matchable

class Any
Show all

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait Serializable

trait Product

trait Equals

trait Kw

class Object

trait Matchable

class Any
Show all

Attributes

Inherited from:: KeywordsStable
Source: Keywords.scala
Supertypes: trait Serializable

trait Product

trait Equals

trait Kw

class Object

trait Matchable

class Any
Show all

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