| MathA built-in object that has properties and methods for mathematical constants and functions. For example, the Math object's PI property has the value of pi.
Core object. | Implemented in | Navigator 2.0, LiveWire 1.0 |
Created byThe Math object is a top-level, predefined JavaScript object. You can automatically access it without using a constructor or calling a method. DescriptionAll properties and methods of Math are static. You refer to the constant PI as Math.PI and you call the sine function as Math.sin(x) , where x is the method's argument. Constants are defined with the full precision of real numbers in JavaScript. It is often convenient to use the with statement when a section of code uses several Math constants and methods, so you don't have to type "Math" repeatedly. For example,with (Math) { a = PI * r*r y = r*sin(theta) x = r*cos(theta) } Property Summary
E
| Euler's constant and the base of natural logarithms, approximately 2.718. | LN10
| Natural logarithm of 10, approximately 2.302. | LN2
| Natural logarithm of 2, approximately 0.693. | LOG10E
| Base 10 logarithm of E (approximately 0.434). | LOG2E
| Base 2 logarithm of E (approximately 1.442). | PI
| Ratio of the circumference of a circle to its diameter, approximately 3.14159. | SQRT1_2
| Square root of 1/2; equivalently, 1 over the square root of 2, approximately 0.707. | SQRT2
| Square root of 2, approximately 1.414. |
Method Summary
abs
| Returns the absolute value of a number. | acos
| Returns the arccosine (in radians) of a number. | asin
| Returns the arcsine (in radians) of a number. | atan
| Returns the arctangent (in radians) of a number. | atan2
| Returns the arctangent of the quotient of its arguments. | ceil
| Returns the smallest integer greater than or equal to a number. | cos
| Returns the cosine of a number. | exp
| Returns Enumber, where number is the argument, and E is Euler's constant, the base of the natural logarithms. | floor
| Returns the largest integer less than or equal to a number. | log
| Returns the natural logarithm (base E) of a number. | max
| Returns the greater of two numbers. | min
| Returns the lesser of two numbers. | pow
| Returns base to the exponent power, that is, base exponent. | random
| Returns a pseudo-random number between 0 and 1. | round
| Returns the value of a number rounded to the nearest integer. | sin
| Returns the sine of a number. | sqrt
| Returns the square root of a number. | tan
| Returns the tangent of a number. |
PropertiesEEuler's constant and the base of natural logarithms, approximately 2.718.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns Euler's constant:function getEuler() { return Math.E } DescriptionBecause E is a static property of Math , you always use it as Math.E , rather than as a property of a Math object you created.LN10The natural logarithm of 10, approximately 2.302.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the natural log of 10:function getNatLog10() { return Math.LN10 } DescriptionBecause LN10 is a static property of Math , you always use it as Math.LN10 , rather than as a property of a Math object you created.LN2The natural logarithm of 2, approximately 0.693.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the natural log of 2:function getNatLog2() { return Math.LN2 } DescriptionBecause LN2 is a static property of Math , you always use it as Math.LN2 , rather than as a property of a Math object you created.LOG10EThe base 10 logarithm of E (approximately 0.434).
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the base 10 logarithm of E :function getLog10e() { return Math.LOG10E } DescriptionBecause LOG10E is a static property of Math , you always use it as Math.LOG10E , rather than as a property of a Math object you created.LOG2EThe base 2 logarithm of E (approximately 1.442).
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the base 2 logarithm of E:function getLog2e() { return Math.LOG2E } DescriptionBecause LOG2E is a static property of Math , you always use it as Math.LOG2E , rather than as a property of a Math object you created.PIThe ratio of the circumference of a circle to its diameter, approximately 3.14159.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the value of pi:function getPi() { return Math.PI } DescriptionBecause PI is a static property of Math , you always use it as Math.PI , rather than as a property of a Math object you created.SQRT1_2The square root of 1/2; equivalently, 1 over the square root of 2, approximately 0.707.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns 1 over the square root of 2:function getRoot1_2() { return Math.SQRT1_2 } DescriptionBecause SQRT1_2 is a static property of Math , you always use it as Math.SQRT1_2 , rather than as a property of a Math object you created.SQRT2The square root of 2, approximately 1.414.
Property of | Math | Static, Read-only | Implemented in | Navigator 2.0, LiveWire 1.0 |
ExamplesThe following function returns the square root of 2:function getRoot2() { return Math.SQRT2 } DescriptionBecause SQRT2 is a static property of Math , you always use it as Math.SQRT2 , rather than as a property of a Math object you created. MethodsabsReturns the absolute value of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxabs(x) Parameters
ExamplesThe following function returns the absolute value of the variable x :function getAbs(x) { return Math.abs(x) } DescriptionBecause abs is a static method of Math , you always use it as Math.abs() , rather than as a method of a Math object you created.acosReturns the arccosine (in radians) of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxacos(x) Parameters
DescriptionThe acos method returns a numeric value between 0 and pi radians. If the value of number is outside this range, it returns 0.Because acos is a static method of Math , you always use it as Math.acos() , rather than as a method of a Math object you created. ExamplesThe following function returns the arccosine of the variable x :function getAcos(x) { return Math.acos(x) } If you pass -1 to getAcos , it returns 3.141592653589793; if you pass 2, it returns 0 because 2 is out of range. See alsoMath.asin , Math.atan , Math.atan2 , Math.cos , Math.sin , Math.tan asinReturns the arcsine (in radians) of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxasin(x) Parameters
DescriptionThe asin method returns a numeric value between -pi/2 and pi/2 radians. If the value of number is outside this range, it returns 0.Because asin is a static method of Math , you always use it as Math.asin() , rather than as a method of a Math object you created. ExamplesThe following function returns the arcsine of the variable x :function getAsin(x) { return Math.asin(x) } If you pass getAsin the value 1, it returns 1.570796326794897 (pi/2); if you pass it the value 2, it returns 0 because 2 is out of range. See alsoMath.acos , Math.atan , Math.atan2 , Math.cos , Math.sin , Math.tan atanReturns the arctangent (in radians) of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxatan(x) Parameters
DescriptionThe atan method returns a numeric value between -pi/2 and pi/2 radians.Because atan is a static method of Math , you always use it as Math.atan() , rather than as a method of a Math object you created. ExamplesThe following function returns the arctangent of the variable x :function getAtan(x) { return Math.atan(x) } If you pass getAtan the value 1, it returns 0.7853981633974483; if you pass it the value .5, it returns 0.4636476090008061. See alsoMath.acos , Math.asin , Math.atan2 , Math.cos , Math.sin , Math.tan atan2Returns the arctangent of the quotient of its arguments.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxatan2(y, x) Parameters
DescriptionThe atan2 method returns a numeric value between -pi and pi representing the angle theta of an (x,y ) point. This is the counterclockwise angle, measured in radians, between the positive X axis, and the point (x,y ). Note that the arguments to this function pass the y-coordinate first and the x-coordinate second.atan2 is passed separate x and y arguments, and atan is passed the ratio of those two arguments.Because atan2 is a static method of Math , you always use it as Math.atan2() , rather than as a method of a Math object you created. ExamplesThe following function returns the angle of the polar coordinate:function getAtan2(x,y) { return Math.atan2(x,y) } If you pass getAtan2 the values (90,15), it returns 1.4056476493802699; if you pass it the values (15,90), it returns 0.16514867741462683. See alsoMath.acos , Math.asin , Math.atan , Math.cos , Math.sin , Math.tan ceilReturns the smallest integer greater than or equal to a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxceil(x) Parameters
DescriptionBecause ceil is a static method of Math , you always use it as Math.ceil() , rather than as a method of a Math object you created. ExamplesThe following function returns the ceil value of the variable x :function getCeil(x) { return Math.ceil(x) } If you pass 45.95 to getCeil , it returns 46; if you pass -45.95, it returns -45. See alsoMath.floor cosReturns the cosine of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxcos(x) Parameters
DescriptionThe cos method returns a numeric value between -1 and 1, which represents the cosine of the angle.Because cos is a static method of Math , you always use it as Math.cos() , rather than as a method of a Math object you created. ExamplesThe following function returns the cosine of the variable x :function getCos(x) { return Math.cos(x) } If x equals Math.PI/2 , getCos returns 6.123031769111886e-017; if x equals Math.PI , getCos returns -1. See alsoMath.acos , Math.asin , Math.atan , Math.atan2 , Math.sin , Math.tan expReturns Ex, where x is the argument, and E is Euler's constant, the base of the natural logarithms.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxexp(x) Parameters
DescriptionBecause exp is a static method of Math , you always use it as Math.exp() , rather than as a method of a Math object you created. ExamplesThe following function returns the exponential value of the variable x :function getExp(x) { return Math.exp(x) } If you pass getExp the value 1, it returns 2.718281828459045. See alsoMath.E , Math.log , Math.pow floorReturns the largest integer less than or equal to a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxfloor(x) Parameters
DescriptionBecause floor is a static method of Math , you always use it as Math.floor() , rather than as a method of a Math object you created. ExamplesThe following function returns the floor value of the variable x :function getFloor(x) { return Math.floor(x) } If you pass 45.95 to getFloor , it returns 45; if you pass -45.95, it returns -46. See alsoMath.ceil logReturns the natural logarithm (base E ) of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxlog(x) Parameters
DescriptionIf the value of number is outside the suggested range, the return value is always -1.797693134862316e+308.Because log is a static method of Math , you always use it as Math.log() , rather than as a method of a Math object you created. ExamplesThe following function returns the natural log of the variable x :function getLog(x) { return Math.log(x) } If you pass getLog the value 10, it returns 2.302585092994046; if you pass it the value 0, it returns -1.797693134862316e+308 because 0 is out of range. See alsoMath.exp , Math.pow maxReturns the larger of two numbers.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxmax(x,y) Parameters
DescriptionBecause max is a static method of Math , you always use it as Math.max() , rather than as a method of a Math object you created. ExamplesThe following function evaluates the variables x and y :function getMax(x,y) { return Math.max(x,y) } If you pass getMax the values 10 and 20, it returns 20; if you pass it the values -10 and -20, it returns -10. See alsoMath.min minReturns the smaller of two numbers.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxmin(x,y) Parameters
DescriptionBecause min is a static method of Math , you always use it as Math.min() , rather than as a method of a Math object you created. ExamplesThe following function evaluates the variables x and y :function getMin(x,y) { return Math.min(x,y) } If you pass getMin the values 10 and 20, it returns 10; if you pass it the values -10 and -20, it returns -20. See alsoMath.max powReturns base to the exponent power, that is, base exponent.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxpow(x,y) Parameters
base | The base number | exponent | The exponent to which to raise base |
DescriptionBecause pow is a static method of Math , you always use it as Math.pow() , rather than as a method of a Math object you created. Examplesfunction raisePower(x,y) { return Math.pow(x,y) } If x is 7 and y is 2, raisePower returns 49 (7 to the power of 2). See alsoMath.exp , Math.log randomReturns a pseudo-random number between 0 and 1. The random number generator is seeded from the current time, as in Java.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0: Unix only Navigator 3.0, LiveWire 1.0: all platforms |
Syntaxrandom() ParametersNone. DescriptionBecause random is a static method of Math , you always use it as Math.random() , rather than as a method of a Math object you created. Examples//Returns a random number between 0 and 1 function getRandom() { return Math.random() } roundReturns the value of a number rounded to the nearest integer.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxround(x) Parameters
DescriptionIf the fractional portion of number is .5 or greater, the argument is rounded to the next highest integer. If the fractional portion of number is less than .5, the argument is rounded to the next lowest integer.Because round is a static method of Math , you always use it as Math.round() , rather than as a method of a Math object you created. Examples//Displays the value 20 document.write("The rounded value is " + Math.round(20.49)) //Displays the value 21 document.write("<P>The rounded value is " + Math.round(20.5)) //Displays the value -20 document.write("<P>The rounded value is " + Math.round(-20.5)) //Displays the value -21 document.write("<P>The rounded value is " + Math.round(-20.51)) In server-side JavaScript, you can display the same output by calling the write function instead of using document.write .sinReturns the sine of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxsin(x) Parameters
DescriptionThe sin method returns a numeric value between -1 and 1, which represents the sine of the argument.Because sin is a static method of Math , you always use it as Math.sin() , rather than as a method of a Math object you created. ExamplesThe following function returns the sine of the variable x :function getSine(x) { return Math.sin(x) } If you pass getSine the value Math.PI/2 , it returns 1. See alsoMath.acos , Math.asin , Math.atan , Math.atan2 , Math.cos , Math.tan sqrtReturns the square root of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxsqrt(x) Parameters
DescriptionIf the value of number is outside the required range, sqrt returns 0. Because sqrt is a static method of Math , you always use it as Math.sqrt() , rather than as a method of a Math object you created. ExamplesThe following function returns the square root of the variable x :function getRoot(x) { return Math.sqrt(x) } If you pass getRoot the value 9, it returns 3; if you pass it the value 2, it returns 1.414213562373095.tanReturns the tangent of a number.
Method of | Math | Static | Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntaxtan(x) Parameters
DescriptionThe tan method returns a numeric value that represents the tangent of the angle.Because tan is a static method of Math , you always use it as Math.tan() , rather than as a method of a Math object you created. ExamplesThe following function returns the tangent of the variable x :function getTan(x) { return Math.tan(x) } If you pass Math.PI/4 to getTan , it returns 0.9999999999999999. See alsoMath.acos , Math.asin , Math.atan , Math.atan2 , Math.cos , Math.sin |
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