EntityClass
Listing of Entity Types »EntityClass[type,name]
represents a class of entities of the specified type identified by name.
EntityClass[type,{property1vspec1,property2vspec2,…}]
represents an implicitly defined entity class containing entities of the specified type for which the properties propertyi conform to the value selector vspeci.
EntityClass[cspec,psel]
represents an entity class with members specified by cspec, selected by the property selector psel.
Details
- Built-in EntityClass objects can be specified with natural language using .
- In EntityClass[type,name], the type can be either a built-in entity type or a type specified in an EntityStore registered with EntityRegister.
- type can be of the form "type" or "type""child1""child2"….
- Implicitly defined entity classes can be resolved into canonically named entities using EntityList[EntityClass[type,{property1value1,property2value2,…}]].
- An implicitly defined entity class represents all entities that fulfill all the specified restrictions on property values.
- Property values in implicitly defined entity classes may make use of Quantity (and intervals of Quantity) for dimensional values, Between for numeric values, DateObject for dates, TakeLargest and TakeSmallest for ordinal selections, and ContainsAll, ContainsExactly, ContainsAny, ContainsOnly, ContainsNone for entities. Lists of entities are interpreted as ContainsAll, while a single entity is interpreted as ContainsAny[{entity}].
- Information of an EntityClass expression will give different properties depending on the EntityTypeName associated with the expression.
Examples
open allclose allBasic Examples (4)
Use the WolframAlpha interface to discover particular entities:
Represent all of the countries in Europe:
Get a list of all the countries:
Get a list of all chemicals that are alcohols:
Get the population of all G7 countries:
A list of available entity classes can be found with EntityClassList:
Create an implicitly defined entity class consisting of all elements whose densities fall within a specified range:
Use an implicitly defined entity class to select the countries with the world's 10 longest borders and return them together with their corresponding border lengths:
Scope (7)
An implicitly defined entity class may be specified using any number of property values:
Return a list of aircraft satisfying the above criteria:
List the entities that simultaneously satisfy a combination of largest and smallest ordinal conditions together with an explicit property value:
List the largest three countries in the Group of 8 by population:
Get information about an EntityClass:
Calculate the mean and standard deviation of the maximum weight for all dog breeds specified by a minimal male height:
Construct an implicitly defined entity class consisting of movies featuring Angelina Jolie:
Retrieve titles, release dates, and posters for these films:
Make a timeline illustrating when these movies were released:
Determine which measurement devices are examples of thermometers:
Applications (7)
Use an implicitly defined entity class consisting of the five longest digestive organs and return them together with their corresponding images:
Use an implicitly defined entity class to find the top 10 sheep breeds sorted by the amount of fleece they produce and return them together with their corresponding images:
Find yellow Pokémon with their body weight between 50 and 100 kg:
Make a collage of their images weighted by their body mass:
Stars with apparent magnitude between and 1:
Find the stars that are among both the 15 nearest and the 15 brightest:
The three largest planets in the solar system:
The closest star to Earth other than the Sun:
The three closest planets to Earth on Jan 3, 2013, sorted by distance:
Find mathematical functions related to the Gudermannian function:
Find mathematical functions with more than 10 named identities:
Text
Wolfram Research (2014), EntityClass, Wolfram Language function, https://reference.wolfram.com/language/ref/EntityClass.html (updated 2019).
CMS
Wolfram Language. 2014. "EntityClass." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2019. https://reference.wolfram.com/language/ref/EntityClass.html.
APA
Wolfram Language. (2014). EntityClass. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/EntityClass.html