talib.BBANDS

```talib.BBANDS()```函数的返回值为：二维数组。该数组包含三个元素分别是：上线数组、中线数组、下线数组。
array

talib.BBANDS(inReal)
talib.BBANDS(inReal, optInTimePeriod)
talib.BBANDS(inReal, optInTimePeriod, optInNbDevUp)
talib.BBANDS(inReal, optInTimePeriod, optInNbDevUp, optInNbDevDn)
talib.BBANDS(inReal, optInTimePeriod, optInNbDevUp, optInNbDevDn, optInMAType)

```inReal```参数用于指定K线数据。
inReal
true
{@struct/Record Record}结构数组、数值数组
```optInTimePeriod```参数用于设置周期，默认值为5。
optInTimePeriod
false
number
```optInNbDevUp```参数用于设置上线乘数，默认值为2。
optInNbDevUp
false
number
```optInNbDevDn```参数用于设置下线乘数，默认值为2。
optInNbDevDn
false
number
```optInMAType```参数用于设置均线类型，默认值为0。
optInMAType
false
number

```javascript
function main() {
    var records = exchange.GetRecords()
    var ret = talib.BBANDS(records)
    Log(ret)
}

import talib
def main():
    records = exchange.GetRecords()
    ret = talib.BBANDS(records.Close)
    Log(ret)

void main() {
    auto records = exchange.GetRecords();
    auto ret = talib.BBANDS(records);
    Log(ret);
}

BBANDS()函数在talib库文档中的描述为：BBANDS(Records[Close],Time Period = 5,Deviations up = 2,Deviations down = 2,MA Type = 0) = [Array(outRealUpperBand),Array(outRealMiddleBand),Array(outRealLowerBand)]