By Islam BarakaDefinitions
In plain terms
It supplies signed one-period movement to RSI, TSI, streak, and other momentum calculations.
Technical
The contract fixes consecutive observation rules, session gaps, adjustment basis, duplicate timestamps, revisions, and the first unavailable row.
Scope
A price difference has price units and is not a percentage return.
Formula
Change_t = Close_t - Close_(t-1)\Delta C_t=C_t-C_{t-1}| Symbol | Meaning | Unit |
|---|---|---|
C_t | current close | price |
C_(t-1) | previous close | price |
Output unit: price
Examples
- A governed lesson calculates or identifies Close-to-Close Change only after its inputs, window, state, scale, and edge cases are declared.
Common misconceptions
- A price difference has price units and is not a percentage return.
Concept relationships
Prerequisites
Required by
- Relative Strength Index
- Positive Gain
- Loss Magnitude
- True Strength Index
- Price Momentum
- Up/Down Streak
- On-Balance Volume
- OBV Close Direction
- OBV Signed Volume
- OBV Cumulative Level
- OBV Initial Seed
- Equal-Close OBV Contribution
- OBV Zero-Volume Contribution
- OBV Level Translation
- OBV Revision Propagation
- OBV Divergence Scope
- Volume Price Trend
- Decimal Close Return
- VPT Volume Contribution
- VPT Cumulative Level
- VPT Positive-Close Constraint
- VPT Zero-Volume Contribution
- VPT Equal-Close Contribution
- VPT Initial Seed
- VPT Adjustment-Basis Sensitivity
- OBV–VPT Magnitude Contrast
- Force Index
- Raw Force
- Price–Volume Unit
- Force EMA Seed
- Force EMA Update
- Force Index Warm-Up
- Force Index Zero-Change State
- Force Index Zero-Volume State
- Force Index Recursive Revision
- Force Index versus VPT
- ZigZag Segmentation
- ZigZag Reversal Fraction
- ZigZag Minimum Bar Separation
- ZigZag Provisional Endpoint
- ZigZag Confirmed Pivot
- ZigZag Searching State
- ZigZag Up Leg
- ZigZag Down Leg
- Inclusive Reversal Threshold
- Strict Extreme Update
- ZigZag Anchor
- ZigZag Alternation Invariant
- ZigZag Reset State
- ZigZag Repaint Scope
- Percentage versus Absolute ZigZag
- Double Top
- Comparable Test Level
- Normalized Level Spread
- Opposing Trough Retracement
- Prior Rise Requirement
- Double Top Neckline
- Neckline Break
- Candidate Availability
- Pattern Confirmation Window
- Double Top Rejection Reason
- Double Bottom
- Comparable Bottom Level
- Opposing Peak Retracement
- Prior Decline Requirement
- Double Bottom Neckline
- Upside Neckline Break
- Bottom Candidate Availability
- Bottom Confirmation Window
- Double-Bottom Rejection Reason
- Double Top–Bottom Polarity
Where this concept is used
- PrerequisiteOn-Balance Volume (OBV)D07-F05-A01
- PrerequisiteVolume Price TrendD07-F05-A05
- PrerequisiteForce IndexD07-F05-A06
- PrerequisiteDouble TopD08-F02-A01
- PrerequisiteDouble BottomD08-F02-A02
Tutorials planned
These catalogued topics use this concept, but their complete build has not shipped yet.
- D07-F03-A01 Prerequisite
- D07-F03-A07 Prerequisite
- D08-F01-A02 Prerequisite
Evidence and governance
- Relative Strength Index TA-Lib · first party technical publication
Supports: preferred label, short definition, technical definition, formula
Limits: Seed, flat-series behavior, unstable periods, and platform compatibility must be frozen before claiming parity.
- Reviewed by
- fintech-builder-batch-008
- Last reviewed
- 2026-07-29
- Next review
- 2027-07-29
- Record status
- published