Example 1: define a column as index pandas
myDataFrame.set_index('column_name')
Example 2: add an index column pandas
import numpy as np
import pandas as pd
df = pd.DataFrame({'month': [2, 5, 8, 10],
'year': [2017, 2019, 2018, 2019],
'sale': [60, 45, 90, 36]})
df.set_index('month')
Example 3: pandas df by row index
indices = [133, 22, 19, 203, 14, 1]
df_by_indices = df.iloc[indices, :]
Example 4: pandas row data to webform
def _getFields(obj, tree=None, retval=None, fileobj=None):
fieldAttributes = {'/FT': 'Field Type', '/Parent': 'Parent', '/T': 'Field Name',
'/TU': 'Alternate Field Name', '/TM': 'Mapping Name', '/Ff': 'Field Flags',
'/V': 'Value', '/DV': 'Default Value'}
if retval is None:
retval = OrderedDict()
catalog = obj.trailer["/Root"]
if "/AcroForm" in catalog:
tree = catalog["/AcroForm"]
else:
return None
if tree is None:
return retval
obj._checkKids(tree, retval, fileobj)
for attr in fieldAttributes:
if attr in tree:
obj._buildField(tree, retval, fileobj, fieldAttributes)
break
if "/Fields" in tree:
fields = tree["/Fields"]
for f in fields:
field = f.getObject()
obj._buildField(field, retval, fileobj, fieldAttributes)
return retval
Example 5: add an index column in range dataframe
df = df.loc[df.index.repeat(df['a'])]
df['c'] = df.groupby(level=0).cumcount() + 1
df = df.reset_index(drop=True)
print (df)
a b c
0 1 x 1
1 2 y 1
2 2 y 2
3 3 z 1
4 3 z 2
5 3 z 3
Example 6: indexing column in pandas
In [8]: age_sex = titanic[["Age", "Sex"]]
In [9]: age_sex.head()
Out[9]:
Age Sex
0 22.0 male
1 38.0 female
2 26.0 female
3 35.0 female
4 35.0 male