How to insert row to dataframe

Question

I have an existing dataframe like this

>>> print(dataframe)
sid
30      11
56       5
73      25
78       2
132      1
        ..
8531    25
8616     2
9049     1
9125     6
9316    11
Name: name, Length: 87, dtype: int64

I want to add a row like {'sid': 2, '': 100} to it but when I try this

df = pandas.DataFrame({'sid': [2], '': [100]})
df = df.set_index('sid')
dataframe = dataframe.append(df)
print(dataframe)

I end up with

sid              
30    11.0    NaN
56     5.0    NaN
73    25.0    NaN
78     2.0    NaN
132    1.0    NaN
...    ...    ...
8616   2.0    NaN
9049   1.0    NaN
9125   6.0    NaN
9316  11.0    NaN
2      NaN  100.0

I'm hoping for something more like

sid
2       100
30      11
56       5
73      25
78       2
132      1
        ..
8531    25
8616     2
9049     1
9125     6
9316    11

Any idea how I can achieve that?

Why doesn't the other series have a name? It'd be better if it did... — AKX
– AKX, Commented Jul 28, 2020 at 11:56
Looks like sid is index name of the series, try dataframe.loc[2] = 100 — anky
– anky, Commented Jul 28, 2020 at 11:58

David · Accepted Answer · 2020-07-28 12:06:57Z

2

The way to do this was

dataframe.loc[2] = 100

Thanks anky!

answered Jul 28, 2020 at 12:06

David

5237 silver badges16 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

yashanmick · Accepted Answer · 2020-07-28 14:23:39Z

Reason for the above problem, because at the time you have appended two DataFrames, you forgot to set 'sid' as the dataframe index. So, basically the two DataFrames has different structure when you append it. Make sure to set the index of both dataframes same before you append them.

data = [ [30,11], [56, 5], [73, 25]]    #test dataframe 
dataframe = pd.DataFrame(data, columns=['sid', ''])
dataframe = dataframe.set_index('sid')
print(dataframe)

You get,

Create and set the index of df,

df = pd.DataFrame({'sid' : [2], '' : [100]})
df = df.set_index('sid')

You get,

sid     
2    100

Then append them,

dataframe = df.append(dataframe)
print(dataframe)

You will get the disired outcome,

Collectives™ on Stack Overflow

How to insert row to dataframe

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related