现在使用自定义因素遇到此问题,它一直在日志中说我有一个错误并且我的数组大小为 0(经过一点回溯测试,我知道这是错误所在)。如果您需要更多信息,请随时询问。
这段代码的目的是创建一个标准化的平均真实范围除以 0-1 比例的价格,我用来编码的源是 quantopian。
确切的错误是:
ValueError: zero-size array to reduction operation fmin which has no identity
class ATrComp(CustomFactor):
inputs = [USEquityPricing.close,USEquityPricing.high,USEquityPricing.low]
window_length = 200
def compute(self, today, assets, out, close, high, low):
hml = high - low
hmpc = np.abs(high - np.roll(close, 1, axis=0))
lmpc = np.abs(low - np.roll(close, 1, axis=0))
tr = np.maximum(hml, np.maximum(hmpc, lmpc))
atr = np.mean(tr[-1:-21], axis=0) #skip the first one as it will be NaN
apr = atr*100 / close[-1]
aprcomp = (apr[-1] - np.amin(apr[-2:-101], axis=0))/(np.amax(apr[-2:-101], axis=0) - np.amin(apr[-2:-101], axis=0))
out[:] = aprcomp
这是代码的不同版本:
class ATrp(CustomFactor):
inputs = [USEquityPricing.close,USEquityPricing.high,USEquityPricing.low]
window_length = 200
def compute(self, today, assets, out, close, high, low):
hml = high - low
hmpc = np.abs(high - np.roll(close, 1, axis=0))
lmpc = np.abs(low - np.roll(close, 1, axis=0))
tr = np.maximum(hml, np.maximum(hmpc, lmpc))
atr = np.mean(tr[-21:], axis=0) #skip the first one as it will be NaN
apr = atr*100 / close[-1]
out[:] = apr
class ATrComp(CustomFactor):
inputs = [USEquityPricing.close,USEquityPricing.high,USEquityPricing.low]
window_length = 200
def compute(self, today, assets, out, close, high, low):
apr = ATrp()
aprcomp = (apr[-1] - np.amin(apr[-2:-101], axis=0))/(np.amax(apr[-2:-101], axis=0) - np.amin(apr[-2:-101], axis=0))
out[:] = aprcomp
这次我的错误是:
TypeError: zipline.pipeline.term.__getitem__() expected a value of
type zipline.assets._assets.Asset for argument 'key', but got int instead.