PSAR (Parabolic SAR)¶
What it shows: a trail of dots below price in an uptrend and above price in a downtrend. The dots move closer to price every candle; when price touches them they flip to the other side.
How people use it: a flip to below price is a buy signal, a flip above a sell signal. Many people use the dots as a trailing stop.
Pairs well with: ADX (Parabolic SAR flips back and forth in sideways markets) and a moving average for direction.
Settings¶
| Setting | Default | What it does |
|---|---|---|
| AF step | 0.02 | How fast the dots speed up toward price. Larger makes them catch price sooner (more, earlier flips; tighter trailing). |
| Max AF | 0.2 | The top speed. Larger lets the dots get very close to price in long trends. Must be larger than AF step. |
You set the defaults on the Indicators page. A condition can use its own settings, which override the defaults for that condition only.
Ready-made conditions¶
| For | Condition | Fires when |
|---|---|---|
| Buy | Parabolic SAR flips to bullish (dots move below price) | the one candle the direction changes to bullish |
| Buy | Parabolic SAR is bullish (dots below price) | every candle SAR is below the price |
| Sell | Parabolic SAR flips to bearish (dots move above price) | the one candle the direction changes to bearish |
| Sell | Parabolic SAR is bearish (dots above price) | every candle SAR is above the price |
"Above", "below", "is" and "rising" / "falling" stay true on every candle the state lasts, so they can fire many candles in a row. "Crosses" and "flips" fire once, on the candle it happens, so you get one signal per move.
Warnings you may see¶
- "PSAR(0.02,0.2) Direction only moves between -1 and 1, so 2 can never be reached.": a number you typed is outside the range this line can take, so the condition can never be true (or is always true). Check the number. You can still save it.
- "It can never be true: a cross happens on one candle, so it cannot happen on N candles in a row. Use 'within the last N candles' instead.": a "crosses" condition with a "… in a row" lookback of 2 or more. Switch the lookback to Within the last.
- "AF step must be between 0.001 and 1": shown in the condition editor when a condition's own value is out of range. Fix the number; the condition can't be saved until then.
- "Max AF must be between 0.001 and 1": shown in the condition editor when a condition's own value is out of range. Fix the number; the condition can't be saved until then.
- "AF step must be smaller than Max AF": in a condition, AF step has to stay below Max AF.
Where they show: on the Strategies page, open Create entry conditions / Edit entry conditions (or the exit ones). Each condition's messages appear right under it. The setting messages ("must be between", "whole number", "must be one of", "must be smaller than") start with the indicator's short name, for example "MACD: Fast must be between 1 and 1000", and keep the conditions from being saved until fixed. The other warnings never block saving and are repeated in the strategy's Entry or Exit section, starting with the condition's name.
Good to know¶
- It is worked out from each candle's high, low and close (not volume).
- It is always in a trade, either up or down, so in sideways markets it flips often.
- It needs some history before its value settles: a fixed 100 candles (its path depends on its first flips). Apathia loads that history for you.
- "Flips" fires once, on the candle the dots switch sides; "is bullish" stays true while they stay below price.