数学符号及其 JavaScript 对应符号列表

Symbol	Name	Since	Example	JavaScript
―	Horizontal bar for division	~1300	ba​	<br>a / b<br>
+	Plus sign	1360	a+b	<br>a + b<br>
-	Minus sign	1489	a−b	<br>a - b<br>
√	Radical symbol	1525	x​	<br>Math.sqrt(x)<br>
(...)	Parentheses	1544	(a+b)	<br>(a + b)<br>
=	Equals	1557	a=b	<br>// equality<br>a == b<br><br>// assignment<br>a = b<br>
.	Decimal separator	1593	1.75	<br>1.75<br>
×	Multiplication sign	1618	a×b	<br>a * b<br>
±	Plus–minus sign	1628	a±2	<br>[a - 2, a + 2]<br>
ⁿ√	Radical symbol for nth root	1629	na​	<br>Math.pow(a, 1/n)<br>
<	Strict inequality less-than	1631	a<b	<br>a < b<br>
>	Strict inequality greater-than	1631	a>b	<br>a > b<br>
xʸ	Superscript notation	1636	ab	<br>a ** b<br>
x	Use of the letter x for an independent variable or unknown value	1637	x	<br>// declare<br>let x = 0<br><br>// usage<br>x<br><br>// re-assign<br>x = 2<br>
%	Percent sign	1650	n%	<br>n / 100<br>
∞	Infinity sign	1655	∞	<br>Infinity<br>
÷	Division sign	1659	a÷b	<br>a / b<br>
≤	Unstrict inequality less-than sign	1670	a≤b	<br>a <= b<br>
≥	Unstrict inequality greater-than sign	1670	a≥b	<br>a >= b<br>
d	Differential sign	1675	m=dxdy​	<br>m = (y2 - y1) / (x2 - x1)<br>
∫	Integral sign	1675	∫18​f(x)⋅dx	<br>let dx = 1/8 // step size<br>let sum = 0<br><br>for (let x=1; x<=8; x += dx) {<br> sum += f(x) * dx<br>}<br>
:	Colon for division	1684	a:b	<br>a / b<br>
·	Middle dot for multiplication	1698	a⋅b	<br>a * b<br>
⁄	Division slash	1718	a/b	<br>a / b<br>
≠	Inequality sign	unknown	a=b	<br>a != b<br>
x'	Prime symbol for derivative	1748	x′	<br>// TODO<br>
Σ	Summation symbol	1755	i=0∑10​i	<br>let sum = 0<br><br>for(let i=0; i<10; i++) {<br> sum += i<br>}<br>
∝	Proportionality sign	1768	yx​αba​	<br>x/y == a/b<br>
∂	Partial differential sign	1770		<br>// TODO<br>
≡	Identity sign	1801	a≡b	<br>a === b<br>
[x]	Integral part (aka floor)	1808	[x]	<br>Math.floor(x)<br>
!	Factorial	1808	n!	<br>function factorial(n) {<br> if (n == 0) return 1<br><br> return n * factorial(n - 1)<br>}<br>
Π	Product symbol	1812	x=2∏4​(x+1)	<br>let product = 1<br>let x = 2<br><br>for (let i=0; i<4; i++) {<br> product *= (x + 1)<br>}<br>
⊂	Set subset of	1817	a⊂b	<br>let a = new Set(...)<br>let b = new Set(...)<br><br>a.isSubsetOf(b)<br>
⊃	Set superset of	1817	a⊃b	<br>let a = new Set(...)<br>let b = new Set(...)<br><br>a.isSupersetOf(b)<br>
|...|	Absolute value notation	1841	∣x∣	<br>Math.abs(x)<br>
‖...‖	Matrix notation	1843	∥x∥	<br>// TODO<br>
∩	Intersection	1888	a∩b	<br>let a = new Set(...)<br>let b = new Set(...)<br><br>a.intersection(b)<br>
∪	Union	1888	a∪b	<br>let a = new Set(...)<br>let b = new Set(...)<br><br>a.union(b)<br>
∈	Membership sign	1894	a∈b	<br>let a = ...<br>let b = new Set(...)<br><br>b.has(a)<br>
{...}	Curly brackets for set notation	1895	{x,y,z}	<br>new Set([x, y, z])<br>
∃	Existential quantifier (there exists)	1897	(∃x) f(x)	<br>let array = [ ... ]<br><br>array.some(x => f(x))<br>
·	Dot product	1902	a⋅b	<br>let a = [...]<br>let b = [...]<br>let sum = 0<br><br>assert(a.length == b.length)<br><br>for (let i=0; i<a.length;i++) {<br> sum += a[i] * b[i]<br>}<br>
×	Cross product	1902	a×b	<br>let a = [x1, y1, z1]<br>let b = [x2, y2, z2]<br><br>[<br> (a[1] * b[2]) - (a[2] * b[1]),<br> (a[2] * b[0]) - (a[0] * b[2]),<br> (a[0] * b[1]) - (a[1] * b[0])<br>]<br>
∨	Logical disjunction (aka OR)	1906	a∨b	<br>a | b<br>
(...)	Matrix round bracket notation	1909	(ax​by​cz​)	<br>[<br> [a, b, c],<br> [x, y, z]<br>]<br>
[...]	Matrix square bracket notation	1909	[ax​by​cz​]	<br>[<br> [a, b, c],<br> [x, y, z]<br>]<br>
∀	Universal quantifier (for all)	1935	(∀x) f(x)	<br>let array = [ ... ]<br><br>array.every(x => f(x))<br>
∅	Empty set sign	1939	∅	<br>new Set()<br>
⌊x⌋	Greatest integer ≤ x (aka floor)	1962	⌊x⌋	<br>Math.floor(x)<br>
⌈x⌉	Smallest integer ≥ x (aka ceiling)	1962	⌈x⌉	<br>Math.ceil(x)<br>

Created by Joshua Nussbaum