code to perform the train test validation split on a pandas dataframe for a time sequence

train_test_val_split_seq.py

trainpct = 0.7
trainidx = int(np.round(len(df)*trainpct))
train_df = df.iloc[0:trainidx,:]

valpct = 0.2
validx = int(np.round(len(df)*(trainpct+valpct)))
val_df = df.iloc[trainidx:validx,:]
             
test_df = df.iloc[validx::,:]


# split data using stratified folds
train_df, temp_df = train_test_split(
    df, 
    test_size=(args.val_split+args.test_split), 
    random_state=4321, 
    shuffle=True, 
    stratify=df['Cover_Type']
)

val_df, test_df = train_test_split(
    temp_df, 
    test_size=(args.test_split/(args.val_split+args.test_split)), 
    random_state=4321, 
    shuffle=True, 
    stratify=temp_df['Cover_Type']
)