我有一个开放/高/低/收盘价的熊猫数据框,我写的是编写一个函数,将抛物线SAR添加到我的数据帧。现在,PSAR数字刚刚变得非常庞大,而且在牛市和熊市方向之间的翻转方面,我似乎也没有太多变化。任何帮助理解为什么我的PSAR变得如此疯狂将是伟大的。我试过这个代码的几个变种无济于事。
对于那些不熟悉PSAR的人:
Current SAR = Prior SAR + Prior AF(Prior EP - Prior SAR)
例如:13-Upper-10:爵士= 48.28 = 48.13 + .14(49.20 - 48.13)
Current SAR = Prior SAR - Prior AF(Prior EP - Prior SAR)
例如:9月2日至10日:SAR = 43.56 = 43.84 - .16(43.84 - 42.07)
在逆转期间,PSAR成为先前的极值点EP,并且新EP是先前的高或低,取决于翻转的方向。 AF重置为0.02。
我的功能:
def addSAR(df):
df.loc[0, 'AF'] =0.02
df.loc[0, 'PSAR'] = df.loc[0, 'low']
df.loc[0, 'EP'] = df.loc[0, 'high']
df.loc[0, 'PSARdir'] = "bull"
for a in range(1, len(df)):
if df.loc[a-1, 'PSARdir'] == 'bull':
df.loc[a, 'PSAR'] = df.loc[a-1, 'PSAR'] + (df.loc[a-1, 'AF']*(df.loc[a-1, 'EP']-df.loc[a-1, 'PSAR']))
df.loc[a, 'PSARdir'] = "bull"
if df.loc[a, 'low'] < df.loc[a-1, 'PSAR']:
df.loc[a, 'PSARdir'] = "bear"
df.loc[a, 'PSAR'] = df.loc[a-1, 'EP']
df.loc[a, 'EP'] = df.loc[a-1, 'low']
df.loc[a, 'AF'] = .02
else:
if df.loc[a, 'high'] > df.loc[a-1, 'EP']:
df.loc[a, 'EP'] = df.loc[a, 'high']
if df.loc[a-1, 'AF'] <= 0.18:
df.loc[a, 'AF'] =df.loc[a-1, 'AF'] + 0.02
else:
df.loc[a, 'AF'] = df.loc[a-1, 'AF']
elif df.loc[a, 'high'] <= df.loc[a-1, 'EP']:
df.loc[a, 'AF'] = df.loc[a-1, 'AF']
df.loc[a, 'EP'] = df.loc[a-1, 'EP']
elif df.loc[a-1, 'PSARdir'] == 'bear':
df.loc[a, 'PSAR'] = df.loc[a-1, 'PSAR'] - (df.loc[a-1, 'AF']*(df.loc[a-1, 'EP']-df.loc[a-1, 'PSAR']))
df.loc[a, 'PSARdir'] = "bear"
if df.loc[a, 'high'] > df.loc[a-1, 'PSAR']:
df.loc[a, 'PSARdir'] = "bull"
df.loc[a, 'PSAR'] = df.loc[a-1, 'EP']
df.loc[a, 'EP'] = df.loc[a-1, 'high']
df.loc[a, 'AF'] = .02
else:
if df.loc[a, 'low'] < df.loc[a-1, 'EP']:
df.loc[a, 'EP'] = df.loc[a, 'low']
if df.loc[a-1, 'AF'] <= 0.18:
df.loc[a, 'AF'] = df.loc[a-1, 'AF'] + 0.02
else:
df.loc[a, 'AF'] = df.loc[a-1, 'AF']
elif df.loc[a, 'low'] >= df.loc[a-1, 'EP']:
df.loc[a, 'AF'] = df.loc[a-1, 'AF']
df.loc[a, 'EP'] = df.loc[a-1, 'EP']
return df
想通了Facepalm
df.loc[a, 'PSAR'] = df.loc[a-1, 'PSAR'] + (df.loc[a-1, 'AF']*(df.loc[a-1, 'EP']-df.loc[a-1, 'PSAR']))
应该是df.loc[a, 'PSAR'] = df.loc[a-1, 'PSAR'] + (df.loc[a-1, 'AF']*(df.loc[a-1, 'PSAR']-df.loc[a-1, 'EP']))
转换最后两个变量!多么痛苦......
现在我可以清理功能并使其更好..
希望这有助于其他人做一些愚蠢的事情,并坚持2天