Venice 0.751beta

nz.org.venice.parser.expression
Class TrendExpression

java.lang.Object
  extended bynz.org.venice.parser.expression.AbstractExpression
      extended bynz.org.venice.parser.expression.TernaryExpression
          extended bynz.org.venice.parser.expression.TrendExpression
All Implemented Interfaces:
java.lang.Cloneable, Expression

public class TrendExpression
extends TernaryExpression

An expression which generates the trend line over the quote and extrapolates the next value.

Author:
Mark Hummel

Field Summary
 
Fields inherited from interface nz.org.venice.parser.Expression
BOOLEAN_TYPE, FALSE, FLOAT_QUOTE_TYPE, FLOAT_TYPE, INTEGER_QUOTE_TYPE, INTEGER_SHORT_TYPE, INTEGER_TYPE, NUMERIC_TYPE, STRING_TYPE, TRUE, TRUE_LEVEL, UNDEFINED_TYPE
 
Constructor Summary
TrendExpression(Expression quote, Expression days, Expression lag)
          Create a new trend expression for the given quote kind, for the given number of days, starting with lag days away, and the given value.
 
Method Summary
 int checkType()
          Perform type checking on the expression.
 java.lang.Object clone()
           
 double evaluate(Variables variables, QuoteBundle quoteBundle, Symbol symbol, int day)
          Evaluates the given expression and returns the result.
 int getType()
          Get the type of the expression.
 java.lang.String toString()
          Convert the given expression to a string.
 
Methods inherited from class nz.org.venice.parser.expression.TernaryExpression
getChildCount
 
Methods inherited from class nz.org.venice.parser.expression.AbstractExpression
equals, getChild, getId, getIndex, getNumberFormat, getParent, getParseMetadata, hashCode, isRoot, iterator, parseDouble, parseInt, printParents, setChild, setChildMutableVersion, setParent, setParseMetadata, simplify, simplifyMutableVersion, size, size, validTree, valueOfDouble, valueOfInt
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

TrendExpression

public TrendExpression(Expression quote,
                       Expression days,
                       Expression lag)
Create a new trend expression for the given quote kind, for the given number of days, starting with lag days away, and the given value.

Parameters:
quote - the quote kind to average
days - the number of days to average over
lag - the offset from the current day
Method Detail

evaluate

public double evaluate(Variables variables,
                       QuoteBundle quoteBundle,
                       Symbol symbol,
                       int day)
                throws EvaluationException
Description copied from interface: Expression
Evaluates the given expression and returns the result.

Parameters:
variables - variable storage area for expression
quoteBundle - the quote bundle containing quote data to use
symbol - the current symbol
day - current date in cache fast access format
Returns:
the result of the expression
Throws:
EvaluationException - if the expression performs an illegal operation such as divide by zero.

toString

public java.lang.String toString()
Description copied from interface: Expression
Convert the given expression to a string.

Specified by:
toString in interface Expression
Overrides:
toString in class AbstractExpression

checkType

public int checkType()
              throws TypeMismatchException
Description copied from interface: Expression
Perform type checking on the expression.

Returns:
the return type of the expression
Throws:
TypeMismatchException - if the expression has incorrect types

getType

public int getType()
Description copied from interface: Expression
Get the type of the expression.

Returns:
one of Expression.BOOLEAN_TYPE, Expression.FLOAT_TYPE, Expression.INTEGER_TYPE, Expression.FLOAT_QUOTE_TYPE or Expression.INTEGER_QUOTE_TYPE.

clone

public java.lang.Object clone()
Specified by:
clone in interface Expression
Specified by:
clone in class AbstractExpression

Venice 0.751beta