Combining dataframes

Concatenation

pd.concat([df1, df2], axis=1) # keeps all cols with axis=1
# Note col names must match if axis = 0

df1.columns = df2.columns

Merge

# colName must be unique
# how = inner, outer (everything), left, right
pd.merge(df1, df2, how='inner', on='colName') 

# left_index = False (can use index over colName)
# left_on = 'colName' (specify the name of the col)

# puts this at the end of the col names that have the same name in both df
# suffixes=('_newLeftColName', '_newRightColName')