Definition:Positive/Rational Number

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Definition

The positive rational numbers are the set defined as:

$\Q_{\ge 0} := \set {x \in \Q: x \ge 0}$

That is, all the rational numbers that are greater than or equal to zero.


Also known as

In order to remove all confusion as to whether positive rational number is intended to mean strictly positive rational number, the use of the term non-negative rational number is often recommended instead.


The $\mathsf{Pr} \infty \mathsf{fWiki}$-specific notation $\Q_{\ge 0}$ is actually non-standard. The conventional symbols to denote this concept are $\Q_+$ and $\Q^+$, but these can be confused with the set $\set {x \in \Q: x > 0}$.


Also see