net.rim.device.api.util
Class MathUtilities

java.lang.Object
  |
  +--net.rim.device.api.util.MathUtilities

public final class MathUtilities
extends Object

Provides some basic numeric operations.


Method Summary
static int clamp(int low, int value, int high)
          Clamps provided value between a lower and upper bound.
static double exp(double x)
          Return the exponential (base e) of x.
static double log(double x)
          Return the natural logarithm (base e) of x.
static int log2(int value)
          Returns the log base 2 of the unsigned value rounded down.
static int log2(long value)
          Returns the log base 2 of the unsigned value rounded down.
static int wrap(int low, int value, int high)
          Wraps provided value around a lower and upper bound.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Method Detail

clamp

public static int clamp(int low,
                        int value,
                        int high)
Clamps provided value between a lower and upper bound.

Note: This method only produces sensible results if the lower bound is less than, or equal to, the higher bound.

Parameters:
low - Lower bound value.
value - Value to clamp.
high - Upper bound value.
Returns:
If the value is lower than the lower bound, this method returns the lower bound; if the value is higher than the higher bound, this method returns the higher bound; otherwise, this method returns the value itself.

exp

public static double exp(double x)
Return the exponential (base e) of x. Interesting cases:
  • If the argument is negative infinity, the result is zero.
  • If the argument is positive infinity, the result is positive infinity.
  • If the argument is NaN, the result is NaN.
  • If the argument is greater than 7.09e+02, the result is positive infinity.
  • If the argument is less than -7.45e+02, the result is zero.
Parameters:
x - the power to raise e to.
Returns:
e raised to the power x.
Since:
JDE 4.2.0

log

public static double log(double x)
Return the natural logarithm (base e) of x. Interesting cases:
  • If the argument is less than zero (including negative infinity), the result is NaN.
  • If the argument is zero, the result is negative infinity.
  • If the argument is positive infinity, the result is positive infinity.
  • If the argument is NaN, the result is NaN.
Parameters:
x - a number greater than zero.
Returns:
the natural logarithm (base e) of the argument.
Since:
JDE 4.2.0

log2

public static int log2(int value)
Returns the log base 2 of the unsigned value rounded down.

The value zero and one both return zero.

Parameters:
value - The unsigned value to calculate log2 on.
Returns:
The calculation of log2(value) (range: 0-31).
Since:
JDE 4.2.0

log2

public static int log2(long value)
Returns the log base 2 of the unsigned value rounded down.

The value zero and one both return a log2 result of zero.

Parameters:
value - The unsigned value to calculate log2 on.
Returns:
The calculation of log2(value) (range: 0-63).
Since:
JDE 4.2.0

wrap

public static int wrap(int low,
                       int value,
                       int high)
Wraps provided value around a lower and upper bound.

Note: This method only produces sensible results if the lower bound is less than, or equal to, the higher bound.

Parameters:
low - Lower bound value.
value - Value to wrap.
high - Upper bound value.
Returns:
If the value is lower than the lower bound, this method returns the higher bound; if the value is higher than the higher bound, this method returns the lower bound; otherwise, this method returns the value itself. This is the opposite of clamp()
Since:
JDE 4.0.0



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