Mathematics in Java
Most of what you need for math in Java is in the Math class.
So, to access these methods, you prepend the name Math
to the method. Most mathematics functions, such as sin, cos, exp, are
written as Math.sin, Math.cos,
Math.exp. The list below summarizes what is available.
CONSTANTS
- e:
Math.E
- Returns a
double representation of the base of the
natural logarithm.
- Pi:
Math.PI
- Returns a
double representation of the ratio of the area
of a circle to its diameter.
- infinity:
Double.POSITIVE_INFINITY
- Returns a
double representation of positive infinity.
- -infinity:
Double.NEGATIVE_INFINITY
- Returns a
double representation of negative infinity.
"
- not a number:
Double.NaN
- Returns a
double representation of an IEEE NaN.
The NaN is often generated during floating point calculations to
signify an exceptional situation. For example, Math.sqrt(-1)
will return a NaN, since Java does not know implicitly
about complex numbers.
FUNCTIONS
- abs
Math.abs(value)
- Returns the absolute integer value of a.
- arc cosine
Math.acos(value)
- Returns the arc cosine of a, in the range of 0.0 through Pi.
- arc sine
Math.asin(value)
- Returns the arc sine of a, in the range of -Pi/2 through Pi/2.
- arc tangent
Math.atan(value)
- Returns the arc tangent of a, in the range of -Pi/2 through Pi/2.
- two argument arc tangent
Math.atan2(x,y)
- Returns the polar angle of the rectangular coordinates (x,y).
- ceiling
Math.ceil(value)
- Returns the smallest whole number greater than or equal to a.
- cosine
Math.cos(value)
- Returns the trigonometric cosine of an angle.
- exp
Math.exp(value)
- Returns the exponential number e(2.718...) raised to the power of a.
- floor
Math.floor(value)
- Returns the "floor" or largest whole number less than or equal to a.
- logarithm
Math.log(value)
- Returns the natural logarithm (base e) of value. To get
base 10
logarithm, use
Math.log(value)/Math.log(10).
- max
Math.max(value_1,value_2)
- Returns the greater of value_1 and value_2.
- min
Math.min(value_1,value_2)
- Returns the lesser of value_1 and value_2.
- power
Math.pow(value_1,value_2)
- Returns value_1 to the power of value_2.
- random number
Math.random()
- Returns a pseudo-random number between 0.0 and 1.0.
- round
Math.round(value)
- Rounds off a floating point value by first adding 0.5 to it and then returning the largest integer that is less than or equal to this new value.
- sine
Math.sin(value)
- Returns the trigonometric sine of an angle.
- sqare root
Math.sqrt(value)
- Returns the square root of a.
- tangent
Math.tan(value)
- Returns the trigonometric tangent of an angle.
David Maxwell,
who is still writing this, would like to
hear your comments and suggestions.
