BUG: Index string ops ignores the order · Issue #10083 · pandas-dev/pandas (original) (raw)

Series (OK)

s = pd.Series(['A', 'B'])
'x' + s
#0    xA
#1    xB
# dtype: object

s + 'y'
#0    Ay
#1    By
# dtype: object

Index (NG)

idx = pd.Index(['A', 'B'])

# NG
'x' + idx
# Index([u'Ax', u'Bx'], dtype='object')

# OK
idx + 'y'
# Index([u'Ay', u'By'], dtype='object')