# Number, Numeric, Quantity

### Table of Contents

## 1 - About

A number is a mathematical object used to:

- count,
- and measure.

When we are interested in the total number of each species of tortoise, or how many individuals there are per square kilometre.

This type of data is called numerical (or quantitative).

## 2 - Articles Related

## 3 - Classification

- Numbers can be classified into set, called numeral system (or system of numeration). It is a mathematical notation system for expressing numbers using digits (or other symbols).
- A field is a collection of “numbers” with the operator: +, -, *, /

## 4 - Categorization

Quantitative variables can be further categorized as either:

- discrete: those that can only have set, integral values, or discrete variables,
- or continuous: those that can be a range of values, or continuous variables. Quantitative Variables can be a range of values, or continuous variables.

## 5 - Extension

In mathematics, the definition of number has been extended over the years to include such numbers as:

- 0,
- negative numbers,
- irrational numbers,
- and complex numbers.

## 6 - Documentation / Related

- See java implement of Number: AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, DoubleAccumulator, DoubleAdder, Float, Integer, Long, LongAccumulator, LongAdder, Short