Abuse of Parentheses
Parentheses are used in... many different ways. I thought I'd collect them.
Name | Usage | Locations (non-exhaustive) |
---|---|---|
Function application | $f(x)$ | Mathematics, programming |
Precedence | $2+(3\cdot5)$ | Mathematics, programming |
Parentheticals | The man (who wore flannel) began ... | Writing |
Ideal | $(N) := \{kN \mid k \in \mathbb Z\}$ | Ring Theory |
Tuples | $(x,y)=(0.5, 1.7)$ | Mathematics, programming |
Indexing | li(i) | MATLAB |
$n$-dimensional sequences | Consider the sequence $(a_{ij})$ ... | Mathematics |
Multiplication | $(5)(17)$ | Mathematics |
S-Expression | (f x y z) | Lisps |
Interval notation | $[2, +\infty)$ | Mathematics |
$n$ choose $k$ | ${n \choose k}$ | Mathematics |
Matrices | $\left( \begin{matrix} 1 & 0 \\ 0 & 1 \end{matrix} \right)$ | Mathematics |
Greatest common divisor | $(a, b) := \mathit{gcd}(a, b)$ | Mathematics |
Generator expression | (f(x) for x in li) | Python |
Function shorthand | (+) , (+2) , (3*) | Haskell |
Congruence | $5 \equiv 15\ (\text{mod } 10)$ | Mathematics |
Labels | See example (B) or refer back to (II) to... | Writing |
Unit | () | Haskell |
Enumeration | Two things: 1) ...; and 2) ... | Writing |
Emojis | :) :( ;) :'( | Texting |