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## org.encog.engine.network.activation
Class ActivationRamp

    java.lang.Object
      org.encog.engine.network.activation.ActivationRamp

All Implemented Interfaces:
  Serializable, Cloneable, ActivationFunction

    public class ActivationRamp

extends Object
implements ActivationFunction

A ramp activation function. This function has a high and low threshold. If the high threshold is exceeded a fixed value is returned. Likewise, if the low value is exceeded another fixed value is returned.

See Also:
  Serialized Form

Field Summary
`static int` | `PARAM_RAMP_HIGH` The ramp high parameter.
`static int` | `PARAM_RAMP_HIGH_THRESHOLD` The ramp high threshold parameter.
`static int` | `PARAM_RAMP_LOW` The ramp low parameter.
`static int` | `PARAM_RAMP_LOW_THRESHOLD` The ramp low threshold parameter.

Constructor Summary
`ActivationRamp()` Default constructor.
`ActivationRamp(double thresholdHigh, double thresholdLow, double high, double low)` Construct a ramp activation function.

Method Summary
`void` | `activationFunction(double[] x, int start, int size)` Implements the activation function.
`ActivationFunction` | `clone()` Clone the object.
`double` | `derivativeFunction(double b, double a)` Calculate the derivative.
`double` | `getHigh()`
`double` | `getLow()`
`String[]` | `getParamNames()`
`double[]` | `getParams()`
`double` | `getThresholdHigh()`
`double` | `getThresholdLow()`
`boolean` | `hasDerivative()`
`void` | `setHigh(double d)` Set the high value.
`void` | `setLow(double d)` Set the low value.
`void` | `setParam(int index, double value)` Set one of the params for this activation function.
`void` | `setThresholdHigh(double d)` Set the threshold high.
`void` | `setThresholdLow(double d)` Set the threshold low.

Methods inherited from class java.lang.Object
`equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### PARAM_RAMP_HIGH_THRESHOLD

    public static final int PARAM_RAMP_HIGH_THRESHOLD

  The ramp high threshold parameter.

  See Also:
    Constant Field Values

### PARAM_RAMP_LOW_THRESHOLD

    public static final int PARAM_RAMP_LOW_THRESHOLD

  The ramp low threshold parameter.

  See Also:
    Constant Field Values

### PARAM_RAMP_HIGH

    public static final int PARAM_RAMP_HIGH

  The ramp high parameter.

  See Also:
    Constant Field Values

### PARAM_RAMP_LOW

    public static final int PARAM_RAMP_LOW

  The ramp low parameter.

  See Also:
    Constant Field Values

Constructor Detail

### ActivationRamp

    public ActivationRamp()

  Default constructor.

### ActivationRamp

    public ActivationRamp(double thresholdHigh,
                          double thresholdLow,
                          double high,
                          double low)

  Construct a ramp activation function.

  Parameters:
    `thresholdHigh` - The high threshold value.
    `thresholdLow` - The low threshold value.
    `high` - The high value, replaced if the high threshold is exceeded.
    `low` - The low value, replaced if the low threshold is exceeded.

Method Detail

### activationFunction

    public final void activationFunction(double[] x,
                                         int start,
                                         int size)

  Implements the activation function. The array is modified according to the activation function being used. See the class description for more specific information on this type of activation function.

  Specified by:
    `activationFunction` in interface `ActivationFunction`
  Parameters:
    `x` - The input array to the activation function.
    `start` - The starting index.
    `size` - The number of values to calculate.

### clone

    public final ActivationFunction clone()

  Clone the object.

  Specified by:
    `clone` in interface `ActivationFunction`
  Overrides:
    `clone` in class `Object`
  Returns:
    The cloned object.

### derivativeFunction

    public final double derivativeFunction(double b,
                                           double a)

  Calculate the derivative. For performance reasons two numbers are provided. First, the value "b" is simply the number that we would like to calculate the derivative of. Second, the value "a", which is the value returned by the activation function, when presented with "b". We use two values because some of the most common activation functions make use of the result of the activation function. It is bad for performance to calculate this value twice. Yet, not all derivatives are calculated this way. By providing both the value before the activation function is applied ("b"), and after the activation function is applied("a"), the class can be constructed to use whichever value will be the most efficient.

  Specified by:
    `derivativeFunction` in interface `ActivationFunction`
  Parameters:
    `b` - The number to calculate the derivative of, the number "before" the activation function was applied.
    `a` - The number "after" an activation function has been applied.
  Returns:
    The derivative.

### getHigh

    public final double getHigh()

  Returns:
    the high

### getLow

    public final double getLow()

  Returns:
    the low

### getParamNames

    public final String[] getParamNames()

  Specified by:
    `getParamNames` in interface `ActivationFunction`
  Returns:
    The names of the parameters.

### getParams

    public final double[] getParams()

  Specified by:
    `getParams` in interface `ActivationFunction`
  Returns:
    The params for this activation function.

### getThresholdHigh

    public final double getThresholdHigh()

  Returns:
    the thresholdHigh

### getThresholdLow

    public final double getThresholdLow()

  Returns:
    the thresholdLow

### hasDerivative

    public final boolean hasDerivative()

  Specified by:
    `hasDerivative` in interface `ActivationFunction`
  Returns:
    True, as this function does have a derivative.

### setHigh

    public final void setHigh(double d)

  Set the high value.

  Parameters:
    `d` - The high value.

### setLow

    public final void setLow(double d)

  Set the low value.

  Parameters:
    `d` - The low value.

### setParam

    public final void setParam(int index,
                               double value)

  Set one of the params for this activation function.

  Specified by:
    `setParam` in interface `ActivationFunction`
  Parameters:
    `index` - The index of the param to set.
    `value` - The value to set.

### setThresholdHigh

    public final void setThresholdHigh(double d)

  Set the threshold high.

  Parameters:
    `d` - The threshold high.

### setThresholdLow

    public final void setThresholdLow(double d)

  Set the threshold low.

  Parameters:
    `d` - The threshold low.

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