nl.liacs.timeseries.main

Class Table

java.lang.Object

java.util.AbstractMap<K,V>

java.util.HashMap<K,V>

java.util.LinkedHashMap<java.lang.String,double[]>

nl.liacs.timeseries.main.Table

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map<java.lang.String,double[]>

public class Table
extends java.util.LinkedHashMap<java.lang.String,double[]>

Table is the construct that holds data.

All data in the Table is stored as double. However, if a time stamp column was found in the original File, a long[] of time stamps may be retrieved. Additionally, if a time stamp column is present, the sampling rate of the data can be requested.

Note the difference between put and add. put will behave exactly as described in the Map interface. add will add a column name-data pair to this Table.

Author:

Marvin Meeng Last updated 06.07.2012

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

java.util.AbstractMap.SimpleEntry<K,V>, java.util.AbstractMap.SimpleImmutableEntry<K,V>

Constructor Summary

Constructors

Constructor and Description
Table(java.io.File theSource, java.lang.String[] theColumnNames, double[][] theData, long[] theTimeStamps) Constructs a Table with its source set by theSource, columns as given by theColumnNames, data as given by theData, and time stamps as given by theTimeStamps.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(java.lang.String[] theColumnNames, double[][] theColumnData) Adds columns to the Table.
int	getNrRows() Returns the number of rows, or records, in this Table.
float	getSamplingRate() Returns the sampling rate (in Hz.) of the data in the Table.
java.lang.String	getSource() Return the full path of the original File that was used to create the Table.
long[]	getTimeStamps() Returns the long[] containing the time stamps.
boolean	hasTimeStamps() Returns true if this Table has a time stamp column, and false otherwise.
double[]	put(java.lang.String theKey, double[] theData) Overridden put() avoids strange misalignments that will occur if external classes call put directly.
boolean	rename(java.lang.String theOldKey, java.lang.String theNewKey) Renames a column.
void	setSamplingRate(float theRate) Sets the sampling rate (in Hz.) of the data in the Table.

Methods inherited from class java.util.LinkedHashMap

clear, containsValue, get

Methods inherited from class java.util.HashMap

clone, containsKey, entrySet, isEmpty, keySet, putAll, remove, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

containsKey, entrySet, equals, hashCode, isEmpty, keySet, putAll, remove, size, values

Constructor Detail

Table

public Table(java.io.File theSource,
     java.lang.String[] theColumnNames,
     double[][] theData,
     long[] theTimeStamps)

Constructs a Table with its source set by theSource, columns as given by theColumnNames, data as given by theData, and time stamps as given by theTimeStamps.

The parameters theSource and theTimeStamps are both optional, and may be null.

See add for restrictions on theColumnNames and theData.

Parameters:

theSource - The File the Table is constructed from.

theColumnNames - The names of the columns to add.

theData - The data for each column to add.

theTimeStamps - The time stamp for the records of the data.

See Also:

FileLoader, add(String[], double[][])

Method Detail

getNrRows

public int getNrRows()

Returns the number of rows, or records, in this Table.

Returns:

The number of rows.

hasTimeStamps

public boolean hasTimeStamps()

Returns true if this Table has a time stamp column, and false otherwise.

The Table has a time stamp column if one of the columns in the File handed to the file loader that created the Table contained data that was successfully parsed as a date format.

Returns:

true iff this Table has a time stamp column, false otherwise.

See Also:

FileLoader

getTimeStamps

public long[] getTimeStamps()

Returns the long[] containing the time stamps.

If hasTimeStamps() evaluates to false, null is returned.

Returns:

The long[] containing the time stamps.

See Also:

hasTimeStamps()

getSamplingRate

public float getSamplingRate()

Returns the sampling rate (in Hz.) of the data in the Table.

The sampling rate it guessed based on the data. If it is incorrect, it can be set by calling setSamplingRate(float).

If hasTimeStamps() evaluates to false, 1.0f is returned.

Returns:

The sampling rate.

See Also:

hasTimeStamps(), setSamplingRate(float)

setSamplingRate

public void setSamplingRate(float theRate)

Sets the sampling rate (in Hz.) of the data in the Table.

If hasTimeStamps() evaluates to false, this method has no real use.

See Also:

hasTimeStamps()

getSource

public java.lang.String getSource()

Return the full path of the original File that was used to create the Table.

Returns:

The full path of the data file, or the empty String if there was an error resolving it.

add

public void add(java.lang.String[] theColumnNames,
       double[][] theColumnData)

Adds columns to the Table.

For this method to succeed, the number of column names must be equal to the number of data columns. Additionally, all data columns must contain the same number of elements.

Columns will be added to the Table by taking the i-th name from theColumnNames, and the corresponding i-th data array from theColumnData.

Parameters:

theColumnNames - The column names.

theColumnData - The column data.

put

public double[] put(java.lang.String theKey,
           double[] theData)

Overridden put() avoids strange misalignments that will occur if external classes call put directly. No data will be added to this Table if the value is not of the correct length. Note that it is impossible to update the Value for a Key, by calling put(Key, newValue).

Specified by:

put in interface java.util.Map<java.lang.String,double[]>

Overrides:

put in class java.util.HashMap<java.lang.String,double[]>

Parameters:

theKey - The key.

theData - The value, or data, associated with the key.

Returns:

The value parameter, or null if it is of incorrect length.

rename

public boolean rename(java.lang.String theOldKey,
             java.lang.String theNewKey)

Renames a column.

This is done by replacing the column with the Key theOldKey, with a column with the Key theNewKey. If the Table does not contain a Key theOldKey, this method returns false.

Parameters:

theOldKey - The old key.

theNewKey - The new key.

Returns:

true iff the renaming operation was successful, false otherwise.