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Homesemimetric

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# semimetric

A semimetric on a set $X$ is a function $d\colon X\times X\to\mathbb{R}$ which satisfies:

1. $d(x,y)\geq 0$

2. $d(x,y)=0$ if and only if $x=y$;

3. $d(x,y)=d(y,x)$.

A semimetric differs from a metric in that the triangle inequality is not required to hold.

Related:

GeneralizationOfAPseudometric

Type of Math Object:

Definition

Major Section:

Reference

## Mathematics Subject Classification

54E25*no label found*

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new collection: On the Information-Theoretic Structure of Distributed Measurements by rspuzio

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new image: plot W(t) = P(waiting time <= t) (2nd attempt) by robert_dodier

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new collection: On the Information-Theoretic Structure of Distributed Measurements by rspuzio

Apr 15

new question: Prove a formula is part of the Gentzen System by LadyAnne

Mar 30

new question: A problem about Euler's totient function by mbhatia

new problem: Problem: Show that phi(a^n-1), (where phi is the Euler totient function), is divisible by n for any natural number n and any natural number a >1. by mbhatia

new problem: MSC browser just displays "No articles found. Up to ." by jaimeglz

Mar 26

new correction: Misspelled name by DavidSteinsaltz

Mar 21

new correction: underline-typo by Filipe

Mar 19

new correction: cocycle pro cocyle by pahio

Mar 7

new image: plot W(t) = P(waiting time <= t) (2nd attempt) by robert_dodier

new image: expected waiting time by robert_dodier