Fill up column based on condition goes wrong-CodePudding

I am trying to fill a column based on condition but something goes wrong.

So I am expecting if it is not 2017 there should be a no.

But yet the years 2019 and 2020 also get filled up with yes.

Does anyone know what went wrong?

``
dfV['is_vacation'] = np.where((dfV['year'] == 2017) & 
                             (dfV['week_nr'] ==  26) & (dfV['week_nr'] ==  27) & (dfV['week_nr'] ==  28)
                              & (dfV['week_nr'] ==  29) & (dfV['week_nr'] == 30) &
                              (dfV['week_nr'] ==  31) & (dfV['week_nr'] ==  32) & (dfV['week_nr'] ==  33) & (dfV['week_nr'] ==  34)
                              & (dfV['week_nr'] ==  35) & (dfV['week_nr'] ==  42) & (dfV['week_nr'] ==  43) & (dfV['week_nr'] ==  44), 'Yes', 'No')
``
``

CodePudding user response：

Use Series.between instead & for bitwise AND, for chain by bitwise OR use |:

dfV = pd.DataFrame({'year':[2017,2018,2019,2017,2017,2017], 
                    'week_nr':[43,30,20,40,30,36]})

dfV['is_vacation'] = np.where((dfV['year'] == 2017) & 
                               (dfV['week_nr'].between(26, 35) | 
                                dfV['week_nr'].between(42, 44)), 
                               'Yes', 'No')
print (dfV)
   year  week_nr is_vacation
0  2017       43         Yes
1  2018       30          No
2  2019       20          No
3  2017       40          No
4  2017       30         Yes
5  2017       36          No

Or:

L = list(range(26, 36))   list(range(42, 45))

dfV['is_vacation'] = np.where((dfV['year'] == 2017) & dfV['week_nr'].isin(L), 
                              'Yes', 'No')