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Math

The Math object always exists in a Qt Script program. Use the Math object to access mathematical constants and functions, e.g.

    with ( Math ) {
        var x = PI * 2;
        var angle = 1.3;
        var 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.

Math Properties

All the Math properties are read-only constants.

Math Functions
abs()

abs( number )

    var x = -99;
    var y = 99;
    with ( Math ) {
        x = abs( x );
        y = abs( y );
    }
    if ( x == y ) System.println( "equal" );

Returns the absolute value of the given number. The equivalent of

    x = x < 0 ? -x : x;
acos()

acos( number )

Returns the arccosine of the given number in radians between 0 and Math.PI. If the number is out of range, returns NaN.

See also cos().

asin()

asin( 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.

See also sin().

atan()

atan( 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.

See also tan() and atan2().

atan2()

atan2( yCoord, xCoord )

Returns the counterclockwise 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 );
    }

See also tan() and atan().

ceil()

ceil( 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

See also floor() and round().

cos()

cos( number )

Returns the cosine of the given number. The value will be in the range -1..1.

See also acos().

exp()

exp( number )

Returns Math.E raised to the power of the given number.

See also log().

floor()

floor( 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.

See also ceil() and round().

log()

log( 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.

See also exp().

max()

max( number1, number2 )

Returns the largest of number1 and number2.

See also min().

min()

min( number1, number2 )

Returns the smallest of number1 and number2.

See also max().

pow()

pow( number, power )

Returns the value of the number raised to the power.

See also sqrt().

random()

random()

Returns a pseudo-random floating point number between 0 and 1. Pseudo random numbers are not truly random, but are often adequate for many applications, for example, games and simulations.

round()

round( 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.

See also ceil() and floor().

sin()

sin( number )

Returns the sine of the given number. The value will be in the range -1..1.

See also asin().

sqrt()

sqrt( number )

If the number is >= 0, it returns the square root. If the number is < 0, it returns NaN.

See also pow().

tan()

tan( number )

Returns the tangent of the given number.

See also atan() and atan2().

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