water.rapids.ast.prims.timeseries

Class AstIsax

java.lang.Object

water.Iced<T>

water.rapids.ast.AstRoot<T>

water.rapids.ast.AstPrimitive

water.rapids.ast.prims.timeseries.AstIsax

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, Freezable

public class AstIsax
extends AstPrimitive

The iSAX algorithm is a time series indexing strategy that reduces the dimensionality of a time series along the time axis. For example, if a time series had 1000 unique values with data across 500 rows, reduce this data set to a time series that uses 100 unique values, across 10 buckets along the time span. References: http://www.cs.ucr.edu/~eamonn/SAX.pdf http://www.cs.ucr.edu/~eamonn/iSAX_2.0.pdf Note: This approach assumes the frame has the form of TS-i x T where TS-i is a single time series and T is time: T-1, T-2, T-3, T-4, ... , T-N TS-1 ... TS-2 ... TS-3 ... . . . TS-N ...

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AstIsax.IsaxReduceCard
static class	AstIsax.IsaxStringTask
static class	AstIsax.IsaxTask

Field Summary

Fields

Modifier and Type	Field and Description
protected double[][]	_domain_hm

Constructor Summary

Constructors

Constructor and Description
AstIsax()

Method Summary

Methods

Modifier and Type	Method and Description
Val	apply(Env env, Env.StackHelp stk, AstRoot[] asts) Primary method to invoke this function, passing all the parameters as the `asts` list.
java.lang.String[]	args() List of argument names.
int	nargs() Number of function's arguments + 1.
java.lang.String	str() String representation of this Ast object in the Rapids language.

Methods inherited from class water.rapids.ast.AstPrimitive

description, example, exec

Methods inherited from class water.rapids.ast.AstRoot

toString

Methods inherited from class water.Iced

asBytes, clone, copyOver, frozenType, read, readExternal, readJSON, reloadFromBytes, toJsonString, write, writeExternal, writeJSON

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

_domain_hm

protected double[][] _domain_hm

Constructor Detail

AstIsax

public AstIsax()

Method Detail

args

public java.lang.String[] args()

Description copied from class: AstPrimitive

List of argument names. The length of the returned array should be equal to `nargs() - 1` (unless `nargs()` returns -1, in which case this function may return {"..."} or something similar).

Specified by:

args in class AstPrimitive

nargs

public int nargs()

Description copied from class: AstPrimitive

Number of function's arguments + 1. Thus, a binary operator like '+' should be declared with 3 nargs: ["+", lhs, rhs]. For variable-argument functions this method should return -1.

Specified by:

nargs in class AstPrimitive

str

public java.lang.String str()

Description copied from class: AstRoot

String representation of this Ast object in the Rapids language. For AstPrimitives this is the name of the function; for AstParameters this is either the name of the variable, or the value of the numeric constant that the parameter represents. For more complicated constructs such as AstExec or AstFunction this method should return those objects as a Rapids string.

Specified by:

str in class AstRoot

apply

public Val apply(Env env,
        Env.StackHelp stk,
        AstRoot[] asts)

Description copied from class: AstPrimitive

Primary method to invoke this function, passing all the parameters as the `asts` list.

Specified by:

apply in class AstPrimitive

Parameters:

env - Current execution environment. Variables are looked up here.

stk - TODO need clarification

asts - List of AstRoot expressions that are arguments to the function. First element in this list is the function itself.

Returns:

value resulting from calling the function with the provided list of arguments.