# Draft:Notations

Notations may be a series or system of written symbols used to represent numbers, amounts, or elements in something such as music or mathematics.

## Astronomy

Notation: let the symbol ${\displaystyle \oplus }$ indicate the Draft:Earth.

Notation: let the symbol ʘ or ${\displaystyle \odot }$ indicate the Sun.

Notation: let the symbol ${\displaystyle I_{\odot }}$ indicate the total solar irradiance.

Notation: let the symbol ${\displaystyle L_{V}}$ indicate the solar visible luminosity.

Notation: let the symbol ${\displaystyle L_{\odot }}$ indicate the solar bolometric luminosity.

Notation: let the symbol ${\displaystyle L_{bol}}$ indicate the solar bolometric luminosity.

Notation: let the symbol ${\displaystyle M_{bol}}$ represent the bolometric magnitude, the total energy output.

Notation: let the symbol ${\displaystyle M_{V}}$ represent the visual magnitude.

Notation: let the symbol ${\displaystyle M_{\odot }}$ indicate the solar mass.

Notation: let the symbol ${\displaystyle Q_{\odot }}$ represent the net solar charge.

Notation: let the symbol ${\displaystyle R_{\oplus }}$ indicate the Earth's radius.

Notation: let the symbol ${\displaystyle R_{J}}$ indicate the radius of Jupiter.

Notation: let the symbol ${\displaystyle R_{\odot }}$ indicate the solar radius.

## Transcriptions start sites

Notation: let the symbol bp indicate a nitrogenous nucleobase pair as linked by a hydrogen bond between the two antiparallel helices that compose DNA.

Notation: let the symbol nt indicate a nucleotide.

Notation: for the coding of individual nucleobases along a DNA strand, the following letters are standardized by convention:

2. cytosine - C,
3. guanine - G, and
4. thymine - T.

Notation: let the subscript (+1) indicate the specific nucleobase along the template strand that is a transcription start site. For example, A+1.

## Degenerate nucleotides

Alphabetically,

IUPAC nucleotide code Base
B C or G or T (U) [not A]
C Cytosine
D A or G or T (U) [not C]
G Guanine
H A or C or T (U) [not G]
K G or T (U) [Keto]
M A or C [aMine]
N aNy base
R A or G [puRine]
S G or C [Strong]
T (or U in RNA) Thymine (or Uracil)
V A or C or G [not T]
W A or T (U) [Weak]
X[1] N, aNy base
Y C or T (U) [pYrimidine]

The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries. IUPAC's Inter-divisional Committee on Nomenclature and Symbols (IUPAC nomenclature) is the recognized world authority in developing standards for the naming of the chemical elements and compounds. Some important work IUPAC has done in these fields includes standardizing nucleotide base sequence code names.

Symbol[2] Description Bases represented
C cytidine C
G guanosine G
T thymidine T
U uridine U
W weak A T 2
S strong C G
M [Amine] amino A C
K [Ketone] keto G T
R [Purine] purine A G
Y [Pyrimidine] pyrimidine C T
B not A (B comes after A) C G T 3
D not C (D comes after C) A G T
H not G (H comes after G) A C T
V not T (V comes after T and U) A C G
N or - any base (not a gap) A C G T 4

These nucleotide notations are an International Union of Pure and Applied Chemistry (IUPAC)[2] representation for a position on a DNA sequence that can be have multiple possible alternatives.

## Semantics

Notation: let the symbol Def. indicate that a definition is following.

## Pragmatics

Notation: let the symbols between [ and ] be replacement for that portion of a quoted text.

Notation: let the symbol ... indicate unneeded portion of a quoted text.

Sometimes these are combined as [...] to indicate that text has been replaced by ....

## Theoretical notations

Notational locations
Weight Oversymbol Exponent
Coefficient Variable Operation
Number Range Index

For each of the notational locations around the central Variable, conventions are often set by consensus as to use. For example, Exponent is often used as an exponent to a number or variable: 2-2 or x2.

In the Notations at the top of this section, Index is replaced by symbols for the Sun (ʘ), Draft:Earth (${\displaystyle R_{\oplus }}$), or can be for Jupiter (J) such as ${\displaystyle R_{J}}$.

A common Oversymbol is one for the average ${\displaystyle {\overline {Variable}}}$.

Operation may be replaced by a function, for example.

All notational locations could look something like

 bx ${\displaystyle -}$ x = n a ${\displaystyle \sum }$ f(x) n → ∞

where the center line means "a x Σ f(x)" for all added up values of f(x) when x = n from say 0 to infinity with each term in the sum before summation multiplied by bn, then divided by n for an average whenever n is finite.

## Mathematics

 ${\displaystyle 1,2,3,\ldots \!}$ ${\displaystyle \ldots ,-2,-1,0,1,2\,\ldots \!}$ ${\displaystyle -2,{\frac {2}{3}},1.21\,\!}$ ${\displaystyle -e,{\sqrt {2}},3,\pi \,\!}$ ${\displaystyle 2,i,-2+3i,2e^{i{\frac {4\pi }{3}}}\,\!}$ Natural numbers Integers Rational numbers Real numbers Complex numbers
A calculator display showing an approximation to the Avogadro constant in E notation. Credit: PRHaney.

## Sciences

Scientific notation (more commonly known as standard form) is a way of writing numbers that are too big or too small to be conveniently written in decimal form. Scientific notation has a number of useful properties and is commonly used in calculators and by scientists, mathematicians and engineers.

Standard decimal notation Normalized scientific notation
2 2×100
300 3×102
4,321.768 4.321768×103
-53,000 −5.3×104
6,720,000,000 6.72×109
0.2 2×10−1
0.000 000 007 51 7.51×10−9

A metric prefix or SI prefix is a unit prefix that precedes a basic unit of measure to indicate a decadic multiple or fraction of the unit. Each prefix has a unique symbol that is prepended to the unit symbol.

Metric prefixes
Prefix Symbol 1000m 10n Decimal Short scale Long scale Since[n 1]
yotta Y 10008 1024 1000000000000000000000000 septillion quadrillion 1991
zetta Z 10007 1021 1000000000000000000000 sextillion trilliard 1991
exa E 10006 1018 1000000000000000000 quintillion trillion 1975
peta P 10005 1015 1000000000000000 quadrillion billiard 1975
tera T 10004 1012 1000000000000 trillion billion 1960
giga G 10003 109 1000000000 billion milliard 1960
mega M 10002 106 1000000 million 1960
kilo k 10001 103 1000 thousand 1795
hecto h 10002/3 102 100 hundred 1795
deca da 10001/3 101 10 ten 1795
10000 100 1 one
deci d 1000−1/3 10−1 0.1 tenth 1795
centi c 1000−2/3 10−2 0.01 hundredth 1795
milli m 1000−1 10−3 0.001 thousandth 1795
micro μ 1000−2 10−6 0.000001 millionth 1960
nano n 1000−3 10−9 0.000000001 billionth milliardth 1960
pico p 1000−4 10−12 0.000000000001 trillionth billionth 1960
femto f 1000−5 10−15 0.000000000000001 quadrillionth billiardth 1964
atto a 1000−6 10−18 0.000000000000000001 quintillionth trillionth 1964
zepto z 1000−7 10−21 0.000000000000000000001 sextillionth trilliardth 1991
yocto y 1000−8 10−24 0.000000000000000000000001 septillionth quadrillionth 1991
1. The metric system was introduced in 1795 with six prefixes. The other dates relate to recognition by a resolution of the General Conference on Weights and Measures (CGPM)]].

## Hypotheses

1. Ancient languages may have been little more than notations.