bbupper
Bollinger upper band
Reference/Bands & channels/Function
bbupper(source, length, mult)
SMA plus multiplier × standard deviation. Short form bbupper(20) uses close and multiplier 2. Sister lines: bbmid, bblower.
Parameters
| Name | Type | Description |
|---|---|---|
sourceoptional | series default close | Series to use. Omit it when the first argument is a number — ema(9) means ema(close, 9). |
length | int default 20 | Lookback in bars. Default 20. |
multoptional | float default 2 | Width in standard deviations. |
Return value
series
Short form: if the first argument is a number, Dovee uses close as the source.
Example
u = bbupper(20) m = bbmid(20) l = bblower(20) plot u as "Upper" red plot m as "Mid" blue plot l as "Lower" green fill u, l blue when close crosses below l then buy