# Triangle Triangle is an indicator on [Vela](https://vela.luxalgo.com/chart), our next-generation charting platform, written in Pine Script®. Detects completed Elliott triangles from the last six swing points, classifying contracting, barrier, expanding and running variants and checking that every leg subdivides into threes. Draws the A-C and B-D boundaries with apex extensions, previews forming structures, and manages the thrust with a widest-part target and invalidation depth, plus eleven alerts. - Indicator in the LuxAlgo Library, by LuxAlgo, published Jun 30, 2026. - Access: free. - Concepts: [Triangle](https://www.luxalgo.com/library/concept/triangle/) (primary) - Open on Vela: https://vela.luxalgo.com/chart?pineScriptCodeId=gdon542cqehun0g8yovlz63q - Page: https://www.luxalgo.com/library/indicator/triangle/ **Triangle** reads the five-legged sideways structure as a wave analyst counts it. Six alternating swing points become A through E, boundaries fit through A-C and B-D, and the shape must satisfy the grammar of the [Elliott triangle](https://www.luxalgo.com/library/concept/triangle/): converging boundaries with shrinking legs (contracting), one flat boundary (barrier), diverging legs (expanding), or a wave B exceeding the start of A (running). ## How to Trade the Triangle? - **Forming preview**: with A through D in place, dotted boundaries and a "triangle forming" tag warn against premature breakout entries while E completes. - **Thrust**: a close through the B-D boundary after E prints the label and projects the target, the widest part times the projection factor, conventionally where profits are taken. - **Invalidation**: a close returning past the invalidation depth, or wave E closing beyond the A-C line past tolerance, marks the count suspect. ## Triangle Settings - **Swing Length** (default 8): pivot length for legs A through E; larger values search higher degrees. - **Sub-Wave Length** (default 3): smaller pivot counting each leg's sub-swings. - **Sub-Wave Validation** (default Loose): Loose rejects clear fives, Strict requires three-consistent counts, Off trusts geometry alone. - **Barrier Flatness %** (default 15): slope budget for a boundary to read as flat. - **Detect Expanding Triangles** (default on): include the rare diverging variant. - **Require Fading Volume & Volatility** (default off): demand a lighter, quieter second half. - **Wave E Overshoot Tolerance** (default 0.25): closing overshoot of the A-C line (fraction of the widest part) voiding the triangle. - **Thrust Projection** (default 1) with **Project Thrust Target** (on) and **Invalidation Depth** (default 0.5): thrust management. - Style: **Wave Labels** (on) and **Show Swings** (on). ## Frequently Asked Questions ### How is this different from the classical triangle pattern? The [Ascending/descending/symmetrical Triangle](https://www.luxalgo.com/library/indicator/ascending-descending-symmetrical-triangle/) build accepts any coil whose closes respect two fitted boundaries. The Elliott definition is stricter (five three-wave legs in an allowed position) and earns a positional message: the thrust is typically the last wave of its sequence. ### Which variant matters most in practice? Contracting triangles are the common form; barrier triangles behave the same with one flat side. Running triangles often read as trend strength; expanding ones resist practical trading. ### Where can a triangle legitimately appear in a count? An impulse's fourth wave, a correction's wave B, or a combination's final structure, never wave 2 on its own. Each pattern's tooltip restates these positions beside the E-to-A ratio. ## Related indicators - [Elliott Wave](https://www.luxalgo.com/library/indicator/elliott-wave/) (Impulse): markdown at https://www.luxalgo.com/library/indicator/elliott-wave.md - [Truncation](https://www.luxalgo.com/library/indicator/truncation/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/truncation.md - [Elliott Hard Rules](https://www.luxalgo.com/library/indicator/elliott-hard-rules/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/elliott-hard-rules.md - [Wave Degree Hierarchy](https://www.luxalgo.com/library/indicator/wave-degree-hierarchy/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/wave-degree-hierarchy.md - [Diagonals](https://www.luxalgo.com/library/indicator/diagonals/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/diagonals.md - [Motive Wave](https://www.luxalgo.com/library/indicator/motive-wave/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/motive-wave.md - [Wave Extension](https://www.luxalgo.com/library/indicator/wave-extension/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/wave-extension.md - [NeoWave Logic](https://www.luxalgo.com/library/indicator/neowave-logic/) (Elliott & Harmonics): markdown at https://www.luxalgo.com/library/indicator/neowave-logic.md --- Source: https://www.luxalgo.com/library/indicator/triangle/ (LuxAlgo Library). Free to use with attribution: https://www.luxalgo.com/library/license/