# Style Guide

Sometimes, when there's no unique way to write something, you need to make a decision. Below are certain rules that I abide by. They are surely arbitrary to some degree, but at least I will stick to one way of doing something.

General rule: US English based on Merriam-Webster.

(Please don't take this as a snobby thing. It's literally just a reminder for myself.)

### Words I hyphen

non-classical

real-world problem

line-source

zeroth-order, first-order, second-order, ...

left-hand side

non-negative

in-scattering

pre-collision

### Words I don't hyphen

path length distribution (not path lengths distribution)

ray effects

test case

phase space

cross section

preprocess

### Referencing and citing

From (1.1) and (1.2) follows ....

I like Table 1.1.

I like Figure 1.1.

I like Algorithm 1.1.

In Appendix A, ...

There are many sections.

I like Section A.

This dates back to the original work by Doe [12].

Ways to solve this problem are presented in [13,132,999].

Previous work [9,2,3] used different approaches.

### Apostrophe

The ball's position. (Ball is singular, apostrophe.)

The balls' positions. (Balls is plural, no apostrophe.)

Thomas's thesis. (No, your English teacher was wrong.)

My Boss's ship. (Just to prove a point)

### Random things

All chapter names have only the first letter capitalized.

True, also for "List of figures", not "List of Figures".

Ph.D. thesis, not PhD thesis

Three things are important: (i) This, (ii) that, and (iii) something else.

(Use i), ii), ... for inline enumerations.)Bla bla, i.e., bla bla. (Two commas.)

Bla bla, e.g., bla bla. (Two commas.)

Bla bla et al.

An adjective, adjective noun. (An expensive, huge smartphone.)

I want to thank you, you, and you. (Oxford comma.)

Bla bla---something in between---bla bla. (Em-dash, no spaces around it.)

spatial discretization

### Math things

Small variables for n_x, n_y, n_q, ...

Order is usually capitalized, i.e., order N

time steps are usually the small n, f^n, f^{n+1}, ...

i,j,k for spatial variables

q for angular variable

If it is an enumeration of equalities, use letter

a = 1 (1.2a)

b= 1 +0 (1.2b)

c= 1 + 2 -2 (1.2c)

or

1 = 1 (1.2a)

= 1 +0 (1.2b)

= 1 + 2 -2 (1.2c)Same for equivalence relations

1=1 (1.1a)

<=>2=2 (1.1b)Use commas this way

1=1

= 1+1,

and

a=1

<=>2a=2,

but

1=1,

2=2,

3=3.If you read it out, it makes sense.

First example: It follows 1 equal to 1 equal to 1+1, thus bla bla.

Second example: It follows a equal to 1 which is equivalent to 2a equal to 2. (This could be debatable though and is a bit motivated by convenience)

Third example: This is an enumeration: We know that 1 equal to 1, 2 equal to 2, and 3 equal to 3.Do not include a number for an equation that has already been mentioned and just gets recalled.

Write non-bold letters for (multi-dimensional) subspaces, e.g. V \subset \mathbb{R}^3.