# Package org.rrd4j.data

RRD4J data management classes and interfaces.
Provides data sources, processors, aggregators, and utilities for Round Robin Database (RRD) operations and calculations.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  IPlottable | Interface for custom data sources used in RRD graphs. Implement this interface to create custom datasources that can be passed to RrdGraphDef for graphing operations.
  NonRrdSource | Interface for non-RRD data sources. Represents computed or derived data sources that don't directly reference RRD data but calculate values from other sources.

- Class Summary
  Class | Description
  --- | ---
  Aggregator | Aggregates RRD data values over specified time periods. Provides statistical aggregation functions for time-series data with configurable time steps and value arrays.
  CDef | RRD CDEF (Computed Data Source Definition) implementation. Creates computed data sources using Reverse Polish Notation (RPN) expressions on existing data sources.
  DataProcessor | Class which should be used for all calculations based on the data fetched from RRD files.
  Def | RRD DEF (Data Source Definition) implementation. Represents a data source defined in an RRD file with specific name, consolidation function, and backend configuration.
  LinearInterpolator | Interpolates datasource values from timestamp-value collections. Suitable for linear interpolation of time-series data points.
  Normalizer | Normalizes RRD data timestamps and values to consistent intervals. Handles alignment of time-series data to ensure regular sampling intervals and proper chronological ordering.
  PDef | RRD PDEF (Plottable Data Source Definition) implementation. Creates data sources from plottable objects that can provide values based on timestamps.
  RpnCalculator | Reverse Polish Notation (RPN) expression calculator. Evaluates mathematical expressions on RRD data sources using RPN notation for efficient computation.
  Source | Abstract base class for RRD data sources. Provides common functionality for storing and managing time-series data with timestamps and values.
  Variable | Abstract class for extracting single values from data sets (VDEF in rrdtool). Provides statistical calculations on RRD values and supports custom computation methods for advanced data processing.
  Variable.AVERAGE | Calculate the average of the data points.
  Variable.ComparPercentElemen | The sort used by rrdtool for percent, where NaN < -INF < finite values < INF
  Variable.FIRST | Find the first valid data point and it's timestamp
  Variable.LAST | Find the first last valid point and it's timestamp
  Variable.LSLCORREL | Calculate the correlation coefficient of the least squares line.
  Variable.LSLINT | Calculate the y-intercept of the least squares line.
  Variable.LSLSLOPE | Calculate the slop of the least squares line.
  Variable.MAX | The biggest of the data points and it's time stamp (the first one) is stored.
  Variable.MIN | The smallest of the data points and it's time stamp (the first one) is stored.
  Variable.PercentElem | Store all the informations about a datasource point, for predictive and consistent sorting
  Variable.PERCENTILE | Find the point at the n-th percentile.
  Variable.PERCENTILENAN |
  Variable.STDDEV | Calculate the standard deviation for the data point.
  Variable.TOTAL | Calculate the sum of the data points.
  Variable.Value | This class store both the value and the time stamp It will be used by graph rendering legend
  VDef | RRD VDEF (Variable Definition) implementation. Creates computed data sources by applying aggregation functions to existing data sources.

- Enum Summary
  Enum | Description
  --- | ---
  LinearInterpolator.Method | A enumeration of interpolation methods

## Package org.rrd4j.data Description

RRD4J data management classes and interfaces.
Provides data sources, processors, aggregators, and utilities for Round Robin Database (RRD) operations and calculations.