48 lines
968 B
Python
48 lines
968 B
Python
import pandas as pd
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class DateFrameHolder:
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def __init__(self, fn):
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self.fn = fn
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self.df = try_load_df(fn)
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def dump(self):
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dump_non_empty_df(self.df, self.fn)
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def append(self, data):
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data = pd.DataFrame.from_records([data])
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self.df = pd.concat([self.df, data], ignore_index=True)
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def clear(self):
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self.df = pd.DataFrame()
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def __repr__(self):
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head = self.fn + ":"
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line = "-" * len(head)
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df = str(self.df)
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return "\n".join((head, line, df))
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def try_load_df(fn):
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try:
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df = pd.read_hdf(fn)
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print(f">>> loaded dataframe from {fn}")
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except FileNotFoundError:
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df = pd.DataFrame()
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print(">>> created empty dataframe")
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return df
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def dump_non_empty_df(df, fn, key="data"):
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if df.empty:
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print("<<< skip dumping empty dataframe")
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return
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print(f"<<< dump dataframe to {fn}")
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df.to_hdf(fn, key)
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