Copyright (C) 2017 J. Patrick Hall, jphall@gwu.edu
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In [2]:
import pandas as pd # pandas for handling mixed data sets
import numpy as np # numpy for basic math and matrix operations
In [3]:
# create a data frame containing variables of disparate scale
scratch_df = pd.DataFrame({'x1': pd.Series(np.random.choice(1000, 20)),
'x2': pd.Series(np.random.choice(20, 20))})
scratch_df
Out[3]:
In [6]:
# create a deep copy
# so this cell can be run many times w/o error
scratch_df1 = scratch_df.copy()
# loop through columns
# create new column
# apply z-score formula to new column
for col_name in scratch_df.columns:
new_col_name = col_name + '_std'
scratch_df1[new_col_name] = (scratch_df[col_name] - scratch_df[col_name].mean())/scratch_df[col_name].std()
# new variables are on the same scale
scratch_df1
Out[6]: