I tried following a tutorial on how to get trends via pandas but I go the error message after I try to show the trends:
ValueError: You must specify a freq or x must be a pandas object with a timeseries index with a freq not set to None
this is my code
import pandas as pd
import datetime
df = pd.read_csv('Sealevel.csv')
df['Time'] = pd.to_datetime(df['Time']
df = df.set_index('Time')
%matplotlib inline
import statsmodels.api as sm
test = sm.tsa.seasonal_decompose(df, model='additive')
fig = test.plot()