MathJax (\$\LaTeX\$ in posts) is live!

Question

We have MathJax

In this meta we discussed, requested, and gathered evidence for the utility of MathJax in RPG.SE posts.

Now it's time to use MathJax

For those familiar with LaTeX it will likely suffice to say that \$ ... \$ are our delimiters ($$ ... $$ for equations centered on their own line), and to let you experiment. Then there's this MathJax reference for your reference, and Math.SE has made a MathJax basic tutorial and quick reference.

Let's put our \$ where our mouths are...

In the previous meta we identified forty-some-odd posts that could benefit from LaTeX treatment. I've copied them below to serve as a punch-list. If you've got five minutes go ahead and edit one, then strike it out on this list. And parse them out over time, to be sure!

List of answers that would might improve with MathJax

[Note: some have found on second pass that an post that looks okay in HTML isn't really worth re-setting into MathJax. I suggest adding "(skipped)" to the end of a link to indicate that the post has been reviewed, but not striking it out in case some later user wants to tilt against that windmill. If you're the original author and think the post should not receive any MathJax I suppose you should either strike it out or remove it wholesale from this list. -nitsua60]

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All done!!

Answer 1

A number of posts would benefit from MathJax's tables, if not its mathematics.

The array environment can do tables quite well. (Thanks nitsua60 for finding this!) Here's an example. Note that because we are \begining an environment, we don't need to have the surrounding $$s.

\begin{array}{r|lll}
\text{Column One} & \text{Two} & \text{Three} & \text{Four} \\
\hline
foo & bar & baz & narf  \\
tinker & tailor & soldier & spy
\end{array}

\begin{array}{r|lll} \text{Column One} & \text{Two} & \text{Three} & \text{Four} \\ \hline foo & bar & baz & narf \\ tinker & tailor & soldier & spy \end{array}

Anatomy of this example:

• \begin{array}{r|lll} comes in two parts:
  • \begin{array} begins the array environment, like it says.
  • {r|lll} sets up our column layout. This means we'll have a right-aligned column, a column divider, then three left-aligned columns. A center-aligned column would be designated with c, and we can have any number of column dividers anywhere we want, including on either side.
• \text{Column One} is an instruction to render “Column One” as plain text. If we didn't include the \text{ ... } marker, it would render as \$Column One\$ instead of as \$\text{Column One}\$. Since MathJax is for writing mathematical formulae it defaults to interpreting symbols you give it as mathematical symbols, ignores spacing and uses its own spacing rules, etc — so it has to be told explicitly when you don't mean that.
• & is the column separator.
• \\ marks a new line at the end of a row.
• \hline marks a horizontal line between rows.
• \end{array} marks the end of the array environment.

As with the rest of the whole MathJax-ificiation, we probably shouldn't actually table-ify anything that's just fine in plain text.

Some potential table-ey posts

• What is the probability of surviving my death saves?
• Considering Complex Dice Roll Probabilities
• Dice pool success probability with one exploding die
• Odds of Tzeentch's Curse in Mass Battles port
• Calculating and balancing challenge ratings

Personal tip: Sublime Text does multi-location and multi-line editing and has made converting posts a breeze so far. (Or at least, not quite so tedious as it could be.)

Answer 2

Since it comes up a fair amount in fantasy settings like Faerûn, handling accents in a MathJax setting (i.e. table) is... awkward. The û character uses the wrong font in MathJax, for example \text{Faerûn} produces \$\text{Faerûn}\$, with the û in a glaringly-different font (non-text contexts are even worse: \$Faerûn\$).

Either accents and diacritics have similar problems: \$ú\$, \$ù\$, \$ü\$, \$ū\$.

MathJax has its own way of doing accents though: \hat, \acute, \grave, \ddot, \bar. So \hat u produces \$\hat u\$. Likewise, \acute u for \$\acute u\$, \grave u for \$\grave u\$, \ddot u for \$\ddot u\$, \bar u for \$\bar u\$.

These can wrap around a text block, for example \hat{\text{u}} produces \$\hat{\text{u}}\$. This gets awkward, though, when you are already in a text context: you have to start a new math context with $ to use \hat, so \$\text{Faer$\hat{\text{u}}$n}\$ requires \text{Faer$\hat{\text{u}}$n}.

Answer 3

Reference for Stack-Useful MathJax structures

Mathematics.SE's meta has a nice post detailing many of the tips they've found useful over the years: https://math.meta.stackexchange.com/questions/5020/mathjax-basic-tutorial-and-quick-reference.

Obviously we should take care around "dialect" issues: their delimiter is $...$, for instance.

TIL you don't even need the \$...\$ delimiters when \begin{...}ing and \end{...}ing an environment!

Answer 4

List of posts identified as candidates, then edited with MathJax:

(per this comment)

• What is your chance to win in a contest where you have advantage and your opponent has disadvantage?
• What is the statistically superior character creation method, twelve 3d6 or six 4d6?
• Does a roleplaying game that uses continuous probability exist?
• How do you calculate an average damage when damage is conditional on circumstances?
• What is the formula for calculating in-system traveling time?
• What happens when you run out of movement while jumping? (skip)
• What is the probability of surviving my death saves?
• Improving "fumbles" when using pools of d10s in TROS
• Improving "fumbles" when using pools of d10s in TROS
• How many rolls does it take to get to six coins? (would appreciate a second set of eyes on this)
• What is the formula for average damage for an Avenger against an Oath target? (skip, spreadsheeting question, mathjax not appropriate)
• What is the formula for average damage for an Avenger against an Oath target? (skip, spreadsheeting question, mathjax not appropriate)
• Is "Unearthed Arcana: Players Make All Rolls" Correct?
• When rolling percentages, do 1d100 and two d10s (percentiles) share the same probabilities?
• How can I test whether a die is fair?
• Can I randomly determine the outcome of an event with 5 outcomes with a d6?
• Improving "fumbles" when using pools of d10s in TROS
• Improving "fumbles" when using pools of d10s in TROS
• Calculating 6D6 similar to poker dice
• How to model a dice pool with re-rolls mechanic?
• Dice probabilities when rolling more dice than needed
• Dealing with large amount of dice rolls for a single damage roll without making it drag on (skip)
• Using AnyDice to determine the odds of getting a specific number sequence on multiple dice (skip)
• Using AnyDice to determine the odds of getting a specific number sequence on multiple dice
• What is the average roll of a die with an expanded explosion threshold as compared to one with an expanded success threshold?
• What is the average roll of a die with an expanded explosion threshold as compared to one with an expanded success threshold?
• Dice pool success probability with one exploding die
• Are Earthdawn's dice mechanics as unfair and wonky as my player claims?
• Are Earthdawn's dice mechanics as unfair and wonky as my player claims?
• How to calculate the expected damage increase from Empowered Spell?
• How much damage does Great Weapon Fighting add on average?
• How much damage does Great Weapon Fighting add on average?
• How do you calculate the odds of success for an ability contest
• Considering Complex Dice Roll Probabilities (skip)
• How do I calculate the chance of hits?
• What's the probability curve of the D10 Storytelling System?
• Does Concentrate Poison Stack?
• How far do you fall per turn?
• Experience point calculation for encounters
• What is the probability of surviving my death saves?
• What is the maximum number of Simulacra I can have? (skip)
• How many rolls does it take to get to six coins?