describe

In machine learning , To get a pile of training data, we usually need to divide the data into training set and test set , Or cut it into training sets 、 Cross validation sets and test sets , In order to avoid bias in feature distribution of the segmented dataset , We need to scramble the data first , Make the data random , And then it's cutting .
The methods to be used are as follows ：
notes ：df Representing one pd.DataFrame

df = df.sample(frac=1.0): Press 100% The proportion of sampling is to achieve the effect of disrupting data

df = df.reset_index()： After scrambling the data index It's also messy , If your index If there is no characteristic meaning , Just reset it , Otherwise, we will put index Add a new column , Generate meaningless index

train = df.loc[0:a]: Carry out segmentation operation , The proportion depends on the situation

cv = df.loc[a+1:b]:

test = df.loc[b+1:-1]: