45 lines
3.0 KiB
TypeScript
45 lines
3.0 KiB
TypeScript
import JsHistogram from "./JsHistogram";
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import { PackedArray } from "./packedarray/PackedArray";
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/**
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* <h3>A High Dynamic Range (HDR) Histogram that uses a packed internal representation</h3>
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* <p>
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* {@link PackedHistogram} supports the recording and analyzing sampled data value counts across a configurable
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* integer value range with configurable value precision within the range. Value precision is expressed as the
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* number of significant digits in the value recording, and provides control over value quantization behavior
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* across the value range and the subsequent value resolution at any given level.
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* <p>
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* {@link PackedHistogram} tracks value counts in a packed internal representation optimized
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* for typical histogram recoded values are sparse in the value range and tend to be incremented in small unit counts.
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* This packed representation tends to require significantly smaller amounts of stoarge when compared to unpacked
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* representations, but can incur additional recording cost due to resizing and repacking operations that may
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* occur as previously unrecorded values are encountered.
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* <p>
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* For example, a {@link PackedHistogram} could be configured to track the counts of observed integer values between 0 and
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* 3,600,000,000,000 while maintaining a value precision of 3 significant digits across that range. Value quantization
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* within the range will thus be no larger than 1/1,000th (or 0.1%) of any value. This example Histogram could
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* be used to track and analyze the counts of observed response times ranging between 1 nanosecond and 1 hour
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* in magnitude, while maintaining a value resolution of 1 microsecond up to 1 millisecond, a resolution of
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* 1 millisecond (or better) up to one second, and a resolution of 1 second (or better) up to 1,000 seconds. At its
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* maximum tracked value (1 hour), it would still maintain a resolution of 3.6 seconds (or better).
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* <p>
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* Auto-resizing: When constructed with no specified value range range (or when auto-resize is turned on with {@link
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* Histogram#setAutoResize}) a {@link PackedHistogram} will auto-resize its dynamic range to include recorded values as
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* they are encountered. Note that recording calls that cause auto-resizing may take longer to execute, as resizing
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* incurs allocation and copying of internal data structures.
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* <p>
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*/
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declare class PackedHistogram extends JsHistogram {
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packedCounts: PackedArray;
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constructor(lowestDiscernibleValue: number, highestTrackableValue: number, numberOfSignificantValueDigits: number);
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clearCounts(): void;
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incrementCountAtIndex(index: number): void;
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addToCountAtIndex(index: number, value: number): void;
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setCountAtIndex(index: number, value: number): void;
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resize(newHighestTrackableValue: number): void;
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getCountAtIndex(index: number): number;
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protected _getEstimatedFootprintInBytes(): number;
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copyCorrectedForCoordinatedOmission(expectedIntervalBetweenValueSamples: number): PackedHistogram;
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toString(): string;
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}
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export default PackedHistogram;
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