首页 > 解决方案 > 在 pandas 中计算 OHLC 数据

问题描述

我有一个 CSV 文件:

_id,ltp,volume,time
5f4dde2e9f742701e3d9a15c,214.55,29077675,2020-09-01T11:07:50.000Z
5f4dde2f9f742701e3d9a15d,214.55,29077690,2020-09-01T11:07:50.000Z
5f4dde2f9f742701e3d9a15e,214.65,29077690,2020-09-01T11:07:51.000Z
5f4dde309f742701e3d9a15f,214.65,29077900,2020-09-01T11:07:51.000Z
5f4dde309f742701e3d9a160,214.6,29077900,2020-09-01T11:07:52.000Z
5f4dde319f742701e3d9a161,214.7,29078191,2020-09-01T11:07:53.000Z
5f4dde329f742701e3d9a162,214.6,29078769,2020-09-01T11:07:54.000Z
5f4dde339f742701e3d9a163,214.65,29078832,2020-09-01T11:07:55.000Z

我需要根据OHLC这些数据计算给定间隔的 。open是区间中的第一个元素,high是最大值,low是最小值,close是最后一个。

这是通过以下与此类似的代码来实现的:

data = df.resample('1T').agg({'ltp': ['first', 'max', 'min', 'last'], 'volume': 'sum'})

问题 1:我无法使用上面的代码将打开、高、低、关闭列分开,它位于“ltp”列内。为了访问open我需要写data['ltp']['first']. (不过这是个小问题可以忽略)

问题 2:主要问题是在计算volume当前我有sum但实际上我想要实现的是这个,例如volumeat 10:01:00is100和 at 10:02:00is 200so total volume for that time frame is 200-100 = 100,我怎么能做到这一点?

标签: pythonpython-3.xpandas

解决方案


对于您的第一个问题,您只需重命名列或删除一个级别。对于第二个问题,取第一个和最后一个并计算差异:

df = pd.DataFrame([["5f4dde2e9f742701e3d9a15c",214.55,29077675,"2020-09-01T11:07:50.000Z"],
["5f4dde2f9f742701e3d9a15d",214.55,29077690,"2020-09-01T11:07:50.000Z"],
["5f4dde2f9f742701e3d9a15e",214.65,29077690,"2020-09-01T11:07:51.000Z"],
["5f4dde309f742701e3d9a15f",214.65,29077900,"2020-09-01T11:07:51.000Z"],
["5f4dde309f742701e3d9a160",214.6,29077900,"2020-09-01T11:07:52.000Z"],
["5f4dde319f742701e3d9a161",214.7,29078191,"2020-09-01T11:07:53.000Z"],
["5f4dde329f742701e3d9a162",214.6,29078769,"2020-09-01T11:07:54.000Z"],
["5f4dde339f742701e3d9a163",214.65,29078832,"2020-09-01T11:07:55.000Z"]], columns = ["_id","ltp","volume","time"])

df["time"] = pd.to_datetime(df["time"])
df = df.set_index("time")
data = df.resample('1S').agg({'ltp': ['first', 'max', 'min', 'last'], 'volume': ['first','last']})

data.columns = ["_".join(x) for x in data.columns.ravel()]
data["volumne_metric"] = data["volume_last"]-data["volume_first"]

输出:

                         ltp_first  ltp_max ltp_min ltp_last volume_first volume_last volumne_metric
time                            
2020-09-01 11:07:50+00:00   214.55  214.55  214.55  214.55  29077675    29077690    15
2020-09-01 11:07:51+00:00   214.65  214.65  214.65  214.65  29077690    29077900    210
2020-09-01 11:07:52+00:00   214.60  214.60  214.60  214.60  29077900    29077900    0
2020-09-01 11:07:53+00:00   214.70  214.70  214.70  214.70  29078191    29078191    0
2020-09-01 11:07:54+00:00   214.60  214.60  214.60  214.60  29078769    29078769    0
2020-09-01 11:07:55+00:00   214.65  214.65  214.65  214.65  29078832    29078832    0

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