javascript Math reference

javascript Math参考

Math Object Methods

FF: Firefox, N: Netscape, IE: Internet Explorer
Method 	Description 	FF 	N 	IE
abs(x) 	Returns the absolute value of a number 	1 	2 	3
acos(x) 	Returns the arccosine of a number 	1 	2 	3
asin(x) 	Returns the arcsine of a number 	1 	2 	3
atan(x) 	Returns the arctangent of x as a numeric value between -PI/2 and PI/2 radians 	1 	2 	3
atan2(y,x) 	Returns the angle theta of an (x,y) point as a numeric value between -PI and PI radians 	1 	2 	3
ceil(x) 	Returns the value of a number rounded upwards to the nearest integer 	1 	2 	3
cos(x) 	Returns the cosine of a number 	1 	2 	3
exp(x) 	Returns the value of Ex 	1 	2 	3
floor(x) 	Returns the value of a number rounded downwards to the nearest integer 	1 	2 	3
log(x) 	Returns the natural logarithm (base E) of a number 	1 	2 	3
max(x,y) 	Returns the number with the highest value of x and y 	1 	2 	3
min(x,y) 	Returns the number with the lowest value of x and y 	1 	2 	3
pow(x,y) 	Returns the value of x to the power of y 	1 	2 	3
random() 	Returns a random number between 0 and 1 	1 	2 	3
round(x) 	Rounds a number to the nearest integer 	1 	2 	3
sin(x) 	Returns the sine of a number 	1 	2 	3
sqrt(x) 	Returns the square root of a number 	1 	2 	3
tan(x) 	Returns the tangent of an angle 	1 	2 	3
toSource() 	Represents the source code of an object 	1 	4 	-
valueOf() 	Returns the primitive value of a Math object 	1 	2 	4

Math Object Properties
Property 	Description 	FF 	N 	IE 
constructor 	A reference to the function that created the object 	1 	2 	4
E 	Returns Euler's constant (approx. 2.718) 	1 	2 	3
LN2 	Returns the natural logarithm of 2 (approx. 0.693) 	1 	2 	3
LN10 	Returns the natural logarithm of 10 (approx. 2.302) 	1 	2 	3
LOG2E 	Returns the base-2 logarithm of E (approx. 1.414) 	1 	2 	3
LOG10E 	Returns the base-10 logarithm of E (approx. 0.434) 	1 	2 	3
PI 	Returns PI (approx. 3.14159) 	1 	2 	3
prototype 	Allows you to add properties and methods to the object 	1 	2 	4
SQRT1_2 	Returns the square root of 1/2 (approx. 0.707) 	1 	2 	3
SQRT2 	Returns the square root of 2 (approx. 1.414) 	1 	2 	3