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DIminus

DIminus in ProBuilder returns the negative directional indicator (DI-) of the ADX system, measuring downward price movement strength. Syntax and examples.

Syntax

probuilder
DIminus[N](price)

Parameters

NameTypeDefaultDescription
Ninteger14Number of periods for the calculation, applied to both the directional movement smoothing and the ATR.
priceprice sourceclosePrice argument passed to the instruction, typically close.

Formula

code
-DM     = previous low - current low   (kept only when positive
                                        and greater than the upward movement, else 0)
DIminus = 100 * WilderSmoothing[N](-DM) / AverageTrueRange[N]

Normalising by the ATR expresses downward movement as a percentage of total range, which makes readings comparable across instruments.

How it works

On each bar, the system measures how far the low undercut the previous low. That amount counts as negative directional movement, but only when it exceeds the bar's upward extension; otherwise the bar contributes zero. The negative movements are smoothed with Wilder's method over N bars, then divided by the ATR over the same window and scaled to 0 to 100.

The resulting line rises when the market repeatedly pushes to lower lows and fades when downward pressure dries up. On its own it says little; the standard reading compares it with DIplus. Whichever line is on top identifies the dominant direction, and crossovers between the two are the classic signal of the Directional Movement System. ADX, computed from the same components, adds the strength dimension.

Examples

Example 1, Plotting both directional lines (Indicator)

probuilder
// 14-period directional indicators on the close
minusLine = DIminus[14](close)
plusLine = DIplus[14](close)
RETURN minusLine COLOURED(200, 50, 50) AS "DI-", plusLine COLOURED(50, 150, 50) AS "DI+"

Displays DI- in red and DI+ in green. The line on top marks the currently dominant direction, and crossings mark potential trend changes.

Example 2, Downtrend screener with strength filter (ProScreener)

probuilder
// Instruments in a confirmed downtrend: DI- above DI+ and ADX above 25
minus = DIminus[14](close)
plus = DIplus[14](close)
trendStrength = ADX[14]
SCREENER[minus > plus AND trendStrength > 25](minus - plus AS "DI- lead")

Lists instruments where downward movement dominates and the ADX confirms the move is strong enough to qualify as a trend, ranked by the DI- lead.

Example 3, Protective exit on a bearish crossover (ProOrder)

probuilder
// Close the long position when DI- overtakes DI+
minus = DIminus[14](close)
plus = DIplus[14](close)

IF LongOnMarket AND minus CROSSES OVER plus THEN
  SELL AT MARKET
ENDIF

Uses the bearish crossover, DI- moving above DI+, as a trend-change exit for an existing long position rather than as an entry signal.

Interpretation

  • DI- above DI+. Downward directional movement dominates. The traditional reading is a downtrend, with confidence increasing when ADX is above roughly 20 to 25.
  • DI- below DI+. Upward movement dominates, bearish pressure is secondary.
  • DI- crossing above DI+. The standard bearish signal of the system, used for short entries or long exits.
  • Absolute level. A high DI- with a low DI+ describes a one-sided decline. Both lines low and close together describes a range.

Common errors and gotchas

  • Reading DI- in isolation. A rising DI- only means lows are being extended. Whether that matters depends on where DI+ sits. Always compare the two lines, or use the combined DI instruction.
  • Crossover direction mix-ups. DI- crossing above DI+ is bearish, not bullish. Because both lines are positive and visually similar, it is a common mistake to invert the condition. Double-check which variable is on which side of CROSSES OVER.
  • Rangebound whipsaws. When ADX is low, the DI lines cross back and forth repeatedly. Filtering crossovers with ADX[14] > 25, as in Example 2, removes most of the churn.
  • Inconsistent periods. DIminus[14] compared against DIplus[20] produces crossings that do not correspond to any standard system. Use the same N for both lines and for ADX.
  • DIplus, the positive counterpart measuring upward movement.
  • DI, single-line difference DI+ minus DI-.
  • ADX, trend strength derived from the DI lines.
  • ADXR, smoothed ADX variant.
  • AverageTrueRange, the volatility normaliser in the formula.
  • TR, single-bar true range.
  • VIminus, negative vortex line, a related downward-movement measure.
  • VIplus, positive vortex line.