(PECL trader >= 0.2.0)
trader_bbands — Bollinger Bands
$real
[, int $timePeriod
[, float $nbDevUp
[, float $nbDevDn
[, int $mAType
]]]] ) : array
real浮点数数组。
timePeriodNumber of period. Valid range from 2 to 100000.
nbDevUpDeviation multiplier for upper band. Valid range from TRADER_REAL_MIN to TRADER_REAL_MAX.
nbDevDnDeviation multiplier for lower band. Valid range from TRADER_REAL_MIN to TRADER_REAL_MAX.
mATypeType of Moving Average. TRADER_MA_TYPE_* series of constants should be used.
Returns an array with calculated data or false on failure.