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The Math object always exists in a Qt Script program. Use the Math object to access mathematical constants and functions, e.g.
var x, angle, y; with ( Math ) { x = PI * 2; angle = 1.3; y = x * sin( angle ); }
The Math object supports all the common mathematical functions, for example: abs(), acos() and cos(), asin() and sin(), atan(), atan2() and tan(), ceil(), floor() and round(), exp() and log(), max() and min(), pow() and sqrt(), random(), and round().
See also, + operator, ++ operator, - operator, -- operator, * operator, / operator, % operator, -= operator, += operator, *= operator, /= operator and %= operator.
All the Math properties are read-only constants.
E -- Euler's constant. The base for natural logarithms.
LN2 -- Natural logarithm of 2.
LN10 -- Natural logarithm of 10.
LOG2E -- Base 2 logarithm of E.
LOG10E -- Base 10 logarithm of E.
PI -- Pi.
SQRT1_2 -- Square root of 1/2.
SQRT2 -- Square root of 2.
abs( number : Number ) : Number;
Returns the absolute value of the given number. The equivalent of
x = x < 0 ? -x : x;
var x = -99; var y = 99; with ( Math ) { x = abs( x ); y = abs( y ); } if ( x == y ) System.println( "equal" );
acos( number : Number ) : Number; Returns the arccosine of the given number in radians between 0 and Math.PI. If the number is out of range, returns NaN.
asin( number : Number ) : Number; Returns the arcsine of the given number in radians between -Math.PI/2 and Math.PI/2. If the number is out of range, returns NaN.
atan( number : Number ) : Number; Returns the arctangent of the given number in radians between -Math.PI/2 and Math.PI/2. If the number is out of range, returns NaN.
atan2( yCoord : Number, xCoord : Number ) : Number; Returns the counter-clockwise angle in radians between the positive x-axis and the point at (xCoord, yCoord). The value returned is always between -Math.PI and Math.PI.
Example:
function polar( x, y ) { return Math.atan2( y, x ); }
ceil( number : Number ) : Number; If the number is an integer, it returns the number. If the number is a floating point value, it returns the smallest integer greater than the number.
Example:
var x = 913.41; x = Math.ceil( x ); // x == 914 var y = -33.97; y = Math.ceil( y ); // y == -33
cos( number : Number ) : Number; Returns the cosine of the given number. The value will be in the range -1..1.
exp( number : Number ) : Number; Returns Math.E raised to the power of the given number.
floor( number : Number ) : Number; If the number is an integer, it returns the number. If the number is a floating point value, it returns the greatest integer less than the number.
log( number : Number ) : Number; If the number is > 0, it returns the natural logarithm of the given number. If the number is 0, it returns Infinity. If the number is < 0, it returns NaN.
max( number1 : Number, number2 : Number ) : Number; Returns the largest of number1 and number2.
min( number1 : Number, number2 : Number ) : Number; Returns the smallest of number1 and number2.
pow( number : Number, power : Number ) : Number; Returns the value of the number raised to the power.
random() : Number; Returns a pseudo-random floating point number between 0 and 1. Pseudo random numbers are not truly random, but may be adequate for some applications, for example, games and simple simulations.
round( number : Number ) : Number; Returns the number rounded to the nearest integer. If the fractional part of the number is >= 0.5, the number is rounded up; otherwise it is rounded down.
sin( number : Number ) : Number; Returns the sine of the given number. The value will be in the range -1..1.
sqrt( number : Number ) : Number; If the number is >= 0, it returns the square root. If the number is < 0, it returns NaN.
tan( number : Number ) : Number; Returns the tangent of the given number.
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