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Given the following text problem statement, write Python code to implement the functionality described below in problem statement
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Problem:
I want to capture an integral of a column of my dataframe with a time index. This works fine for a grouping that happens every time interval.
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Python Code:
import pandas as pd
import io
from scipy import integrate
string = '''
Time                      A
2017-12-18-19:54:40   -50187.0
2017-12-18-19:54:45   -60890.5
2017-12-18-19:54:50   -28258.5
2017-12-18-19:54:55    -8151.0
2017-12-18-19:55:00    -9108.5
2017-12-18-19:55:05   -12047.0
2017-12-18-19:55:10   -19418.0
2017-12-18-19:55:15   -50686.0
2017-12-18-19:55:20   -57159.0
2017-12-18-19:55:25   -42847.0
'''
df = pd.read_csv(io.StringIO(string), sep = '\s+')
df.Time = pd.to_datetime(df.Time, format='%Y-%m-%d-%H:%M:%S')
df = df.set_index('Time')
integral_df = df.rolling('25S').apply(integrate.trapz)
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