Number, Numeric, Quantity

1 - About

A number is a mathematical object used to:

Example: 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 commonly:

  • numerical data
  • or quantitative data.

The same number may be:

3 - Notion

3.1 - Number System

Numbers can be classified into set, called number system.

The most common number system (ie number classification) are:

3.2 - Numeral System

Numbers can be expressed (ie written) into set, called numeral system (or system of numeration). It is a mathematical notation system for expressing numbers using digits (or other symbols).

Example of numeral system (ie number representation)]]:

3.3 - Number Storage

Numbers can be stored in:

However, since division almost immediately introduces infinitely repeating sequences of digits (such as 4/7 in decimal, or 1/10 in binary), the representation would be:

  • truncated at some satisfactory size
  • or else rational numbers would be used: a large integer for the numerator and for the denominator. But even with the greatest common divisor divided out, arithmetic with rational numbers can become unwieldy very quickly: 1/99 – 1/100 = 1/9900, and if 1/101 is then added the result is 10001/999900.

(From Arbitrary-precision_arithmetic)

3.4 - Field

A field is a collection of “numbers” with their operator: +, -, *, /

3.5 - Discrete / Continous

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.

4 - Documentation / Related

  • See java implement of Number: AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, DoubleAccumulator, DoubleAdder, Float, Integer, Long, LongAccumulator, LongAdder, Short
data/type/number/number.txt · Last modified: 2017/09/13 16:06 by gerardnico