User:MathMartin/Styleguide

From Wikipedia, the free encyclopedia

Contents

[edit] Language

"An unitary" or "an union" or "an university" were used in the 18th century, but now "a" rather than "an" is standard when the initial sound is "yoo".

[edit] Naming convention

N(x) := \sum_{j=0}^{k} a_{j} \prod_{i=0}^{j} (x - x_{i-1})

[edit] HTML math

[edit] Minus sign

Use [−1,1] instead of [-1,1]. The little hyphen is too short to be a minus sign.

[edit] TeX

[edit] Colon

f\colon (0,1)\rightarrow\mathbb{R}

instead of

f:(0,1)\rightarrow\mathbb{R}

[edit] Mapping arrows

When you want to define the domain and codomain of the mapping use

\mathrm{sq}:\mathbb R\to\mathbb R

but when you define the actual mapping function use

x\mapsto x^2.

[edit] Standard function names

Use

eix = cosx + isinx

instead of

eix = cosx + isinx

to prevent the function names from looking like a variable.

[edit] Imaginary unit

The imaginary unit i should not be confused with the common variable i. So to make the imaginary unit look different it is better to write

eix = cosx + isinx

than

eix = cosx + isinx

[edit] Embedded fractions

When a fraction is in a superscript or otherwise deeply embedded within some other notation, it is often more legible like this

e^{-x^2/2}

than like this

e^{-x^2 \over 2}

[edit] Spacing

[edit] Integrals

Use

\int f(x)\, dx

rather than

\int f(x) dx

[edit] Sets defined by using braces

This is another place where small spacing adjustments make notation look better. This

\{\,f(x) : 0<x<2\,\}

is better than this

{f(x):0 < x < 2}