Momentum and oscillators

Momentum functions describe price change, strength or location within a recent range. Their scales differ: compare RSI with an RSI threshold, MACD with a price-unit value, and ROC with percentage points.

RSI

rsi(14) calculates Relative Strength Index from close using a 14-bar period and Wilder smoothing. It returns a series on a 0–100 scale. rsi(close, 14) is the explicit equivalent; rsi(close) uses the default period of 14.

rsi(14) > 50
rsi(14) < 30
rsi(14) > rsi(14)[1]
rsi(high, 14) > 50

The first test selects readings above 50. The second selects readings below 30; it does not mean price must rebound. The third asks whether the reading rose since the previous bar. The final call changes the input from close to high.

In rsi(14) < 30, 14 is the calculation period; 30 is your rule's threshold. A reading of 30 is not a 30% loss. RSI starts with a missing first reading; in this implementation a completely flat price sequence subsequently reads 0, while gains without losses read 100. Check warmup rather than treating an initial extreme as a mature signal.

See RSI mean reversion for a complete strategy with explained entry and exit rules.

MACD, signal and histogram

The three functions use the same arguments: fast EMA period, slow EMA period, signal EMA period. Defaults are 12, 26, 9. Each returns one series in price units.

Function	Meaning	Call
macd	Fast EMA minus slow EMA.	macd(12, 26, 9)
macd_signal	EMA of the MACD line.	macd_signal(12, 26, 9)
macd_hist	MACD minus its signal.	macd_hist(12, 26, 9)

macd(12, 26, 9) > macd_signal(12, 26, 9)
macd(12, 26, 9) crosses over macd_signal(12, 26, 9)
macd_hist(12, 26, 9) > 0

Use the same settings on both lines when describing one MACD system. A positive histogram means MACD is above signal; it does not necessarily mean MACD itself is positive. For default settings with an explicit input, use macd(close), macd_signal(close) or macd_hist(close). Empty calls do not select close. Do not use .signal or tuple unpacking.

Price change: ROC, momentum and PPO

Function	Form and defaults	Result
roc	roc(14) or roc(close, 14); default period 14.	100 × (current − earlier) / earlier, in percentage points.
momentum	momentum(14) or momentum(close, 14); supply the period explicitly.	Current price minus price N bars ago, in price units.
ppo	ppo(12, 26) or ppo(close, 12, 26); defaults 12, 26 with explicit input.	100 × (fast EMA − slow EMA) / slow EMA.

If price rises from 100 to 105 over 14 bars, ROC is 5 and momentum is 5 price units. If it rises from 1,000 to 1,050, ROC is still 5, while momentum is 50. To compare price-relative change across instruments, use ROC rather than absolute momentum. momentum_rank is a separate portfolio-ranking function.

roc(14) > 5
momentum(14) > 0
ppo(12, 26) > 0

Use momentum, not the catalog-only abbreviation mom; the standard runtime does not bind mom. Momentum at offset N requires N+1 prices. The helpers page explains why pct_change uses 0.05 for the same 5% change.

Stochastic and Williams %R

These compare close with the recent high–low range and therefore need complete bars.

Function	Form and defaults	Result
stochastic, stochastic_k	stochastic(14, 3, 1); lookback 14, %D smoothing 3, multiplier 1.	The %K series, normally 0–100 at multiplier 1. Both names select the same line.
stochastic_d	stochastic_d(14, 3, 1)	The 3-bar SMA of %K with those settings.
williams_r	williams_r(14); default 14.	Series from −100 to 0. Near 0 is near the range high.

stochastic_k(14, 3) crosses over stochastic_d(14, 3)
stochastic(14) < 20
williams_r(14) < -80

The stochastic multiplier scales both lines: changing it changes the appropriate thresholds. Williams %R uses negative readings; writing williams_r(14) < 80 is a very different test from < -80. Both ranges include the current bar. Empty calls use default settings and automatically select the complete bars for this family.

CCI and other oscillators

Function	Form	Meaning and settings
cci	cci(20, 0.015)	Commodity Channel Index: typical-price deviation from its average, scaled by mean absolute deviation and the constant. Defaults 20 and 0.015. Unbounded series; ±100 are reference levels, not limits.
tsi	tsi(25, 13)	True Strength Index: double-smoothed price change divided by double-smoothed absolute change, ×100. Periods default to 25, 13 with explicit close.
rmi	rmi(bars, 14, 5)	Relative Momentum Index: 14-period smoothing of 5-bar price changes. Defaults 14, 5 after explicit bars; normally 0–100.
awesome	awesome(bars, 5, 34)	Fast minus slow SMA of midpoint (high + low) / 2, in price units. Defaults 5, 34 after explicit bars.
stc	stc(bars, 23, 50, 10)	Schaff Trend Cycle: fast EMA period, slow EMA period, cycle window. Defaults 23, 50, 10; a normalised, smoothed cycle series.
modified_stochastic	modified_stochastic(bars, 14)	Applies extra smoothing to %K, using %D period 3 internally; default lookback 14 after explicit bars. May overshoot.

cci(20) > 100
tsi(25, 13) > 0
rmi(bars, 14, 5) > 50
awesome(bars, 5, 34) > 0
stc(bars, 23, 50, 10) > 50
modified_stochastic(bars, 14) > 50

Keep the explicit bars argument on rmi, awesome, stc and modified_stochastic: period-only shorthand is not implemented for those names. Unlike a bounded oscillator, CCI can exceed 100 or fall below −100. Extra smoothing does not make a threshold equivalent to that of the unsmoothed indicator.

modified_rsi is an exposed extra-smoothed RSI function, but it currently produces missing readings on ordinary close history, even after a long warmup. Use rsi for working rules until that calculation is corrected. Its period default is 14.

trix currently returns multiple lines without an exposed single-line TradeScript function. See special cases before using that name.