# indicator function

> function that returns 1 if an element is present in a specified subset and 0 if absent; naturally isomorphic with a set's subsets

**Wikidata**: [Q371983](https://www.wikidata.org/wiki/Q371983)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Indicator_function)  
**Source**: https://4ort.xyz/entity/indicator-function


## References

1. Freebase Data Dumps. 2013