我对此感到挠头,因为我真的很困惑。
我正在尝试计算一个numpy数组的移动平均值。 numpy数组是从txt文件加载的。

我还尝试打印我的smas函数(我在加载的数据上计算的移动平均值),但没有这样做!

这是代码。

def backTest():
    portfolio = 50000
    tradeComm = 7.95

    stance = 'none'
    buyPrice = 0
    sellPrice = 0
    previousPrice = 0

    totalProfit = 0

    numberOfTrades = 0
    startPrice = 0


    startTime = 0
    endTime = 0
    totalInvestedTime = 0
    overallStartTime = 0
    overallEndTime = 0

    unixConvertToWeeks = 7*24*60*60
    unixConvertToDays = 24*60*60
    date, closep, highp, lowp, openp, volume = np.genfromtxt('AAPL2.txt', delimiter=',', unpack=True,
                                                          converters={ 0: mdates.strpdate2num('%Y%m%d')})


    window = 20
    weights = np.repeat(1.0, window)/window
    smas = np.convolve(closep, weights, 'valid')

    prices = closep[19:]

    for price in prices:
        if stance == 'none':
            if prices > smas:
                print "buy triggered"
                buyPrice = closep
                print "bought stock for", buyPrice
                stance = "holding"
                startTime = unixStamp
                print 'Enter Date:', time.strftime('%m/%d/%Y', time.localtime(startTime))

            if numberOfTrades == 0:
                startPrice = buyPrice
                overallStartTime = unixStamp

            numberOfTrades += 1


        elif stance == 'holding':
            if prices < smas:
                print 'sell triggered'
                sellPrice = closep
                print 'finished trade, sold for:',sellPrice
                stance = 'none'
                tradeProfit = sellPrice - buyPrice
                totalProfit += tradeProfit
                print totalProfit
                print 'Exit Date:', time.strftime('%m/%d/%Y', time.localtime(endTime))
                endTime = unixStamp
                timeInvested = endTime - startTime
                totalInvestedTime += timeInvested

                overallEndTime = endTime

                numberOfTrades += 1

        previousPrice = closep


这是错误:

 Traceback (most recent call last):
  File "C:\Users\antoniozeus\Desktop\backtester2.py", line 180, in <module>
backTest()
  File "C:\Users\antoniozeus\Desktop\backtester2.py", line 106, in backTest
if prices > smas:
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

最佳答案

如果您有一维一维的numpy数组,那么有一种非常巧妙的方式使用累积量(通过https://stackoverflow.com/a/14314054/1345536)进行移动平均:

def moving_average(a, n=3) :
    ret = np.cumsum(a, dtype=float)
    ret[n:] = ret[n:] - ret[:-n]
    return ret[n - 1:] / n


您的代码段中有很多与手头问题无关的代码。

关于python - python错误-numpy数组上的移动平均值,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/22885899/

10-11 21:50