Use this tag for pandas.DataFrame.fillna or pandas.Series.fillna
Fill missing values using the specified method for a DataFrame or a Series with pandas (see also interpolate, ffill, bfill)
Docs:
Questions tagged [fillna]
528 questions
2
votes
2 answers
pandas, how only fillna for last row with preceding line closest non-nan value
import pandas as pd
import numpy as np
df = pd.DataFrame(np.random.randint(0, 10, (10, 10)), columns=list('ABCDEFGHIJ'))
df[df > 5] = np.nan
for i in range(10):
df.iloc[i, i % 10] = np.nan
print(df)
origin df is:
A B C D E …
Zheng Xiaodong
- 143
- 3
- 9
2
votes
1 answer
Replace NaN values in a Dataframe with average of same column with the same value from another column
I have a pandas dataframe that consists of multiple columns. For this question we only need to focus on the "Cholesterol" and "Age" column.
In this dataframe each row represents a person and they all have an age. The Cholesterol column has a lot of…
Thomas Marsden
- 56
- 6
2
votes
1 answer
How can I replace a nan value in an "object" column?
How can I replace a nan value in a column which is an 'object', contains other str and ensure it goes into the main df and not just the slice.
I have tried this
covid_19_df.Country_code.fillna('OT')
but it is still empty
D Country_code …
Nuro
- 23
- 5
2
votes
3 answers
Fill NAs : Min of values in group
Here is my DataFrame.
df = pd.DataFrame ( {'CNN': ['iphone 11 63 GB TMO','iphone 11 128 GB ATT','iphone 11 other carrier','iphone 12 256 GB TMO','iphone 12 64 GB TMO','iphone 12 other carrier'],
'Family Name':['iphone…
Daman deep
- 631
- 3
- 14
2
votes
2 answers
How to fill the gaps, and assigne the values, when using cumulative sum with Pandas?
I have following dataset (much larger, this is just small sample from it):
City Year Votes
Detroit 1964 23
Detroit 1977 61
Detroit 1978 89
Detroit 1986 116
Detroit 1993 144
Baltimore 1964 42
Baltimore 1965 91
Baltimore…
botafogo
- 189
- 7
2
votes
3 answers
R Fill NA with last value for a max of n times
There are multiple ways to fill missing values in R. However, I can't find a solution for filling just the last n NAs.
Available options:
na_vector <- c(1, NA, NA, NA, 2, 3, NA, NA)
library(zoo)
na.locf(na_vector)
# Outputs: [1] 1 1 1 1 2 3 3…
Pedro Teles
- 47
- 5
2
votes
2 answers
Pandas fillna with custom lamda function - output not displayed correctly
I have two dataframes. The first one, grouper contains the mean sales quantity per month by item. Most items have values for all 12 months, because they have been sold for > 1 year. But the items that have been on sale < 1 year do not have values…
asuidncsdk
- 67
- 8
2
votes
7 answers
How to efficiently fill a column of a dataframe based on a dictionary
I have a dataframe and dictionary like this
import pandas as pd
import numpy as np
df = pd.DataFrame({
'A': [1, 1, 1, 2, 2, 3, 3, 3, 3],
'ignore_me': range(9),
'fill_me': [np.nan] * 9
})
di = {
1: ['a', 'b'],
2: ['c', 'd'],
…
Cleb
- 25,102
- 20
- 116
- 151
2
votes
2 answers
Faster alternative to groupby, unstack then fillna
I'm currently doing the following operations based on a dataframe (A) made of two columns with multiple thousands of unique values each.
>>> pd.DataFrame({
'col1': ['foo', 'bar', 'bar', 'foo', 'baz', 'bar', 'baz'],
'col2': ['abc', 'def',…
Jivan
- 21,522
- 15
- 80
- 131
2
votes
1 answer
Pandas DataFrame conditional forward filling based on first row values
I have the following DataFrame:
import pandas as pd
df = pd.DataFrame({
'col1':['A',pd.NA,pd.NA,pd.NA,pd.NA, 'B', pd.NA, pd.NA],
'col2':[9.5, 6,24,8, 30, 7, 6, 8],
})
print(df)
Giving:
col1 col2
0 A 9.5
1 6.0
2 …
McBuch
- 43
- 6
2
votes
2 answers
Filling blanks in a pandas dataframe column leads to reversal of function
I have the following dataframe:
a b x y language
0 id1 id_2 3
1 id2 id_4 6 ,0=/%
2 id3 id_6 9 |-|/#
3 id4 id_8 12 text4
I used langdetect to detect the language of the text elements in column y.
This is the code I…
Tipo33
- 181
- 13
2
votes
1 answer
Pandas fillna() rows in a specific order
I have problem with fillna() method. This is my example df, which represents quantity of items in a shop. I would like to fill all the NaNs. If there is a NaN, I would like to fill it with values from previous day or if it is NaN, then from the next…
kstajer
- 55
- 4
2
votes
2 answers
Filling Missing Values Based on String Condition
I'm trying to write a function to impute some null values from a Numeric column based on string conditions from a Text column.
My attempt example:
def fill_nulls(string, val):
if df['TextColumn'].str.contains(string) == True:
df['NumericColumn']…
Electronic_Tear
- 61
- 5
2
votes
1 answer
Fill nan value when condition meet
I have a dataframe as shown below:
df = pd.DataFrame({'A': [1, np.nan, np.nan, np.nan, 3, 3, 3, 3, np.nan, np.nan, np.nan, 5, 5, 5, 6, 6, 6, np.nan, np.nan, np.nan, 6, 7, 8, 9, 10,np.nan, np.nan, 10, 11]})
I wanna fill the nan value only when the…
Ali
- 113
- 4
2
votes
3 answers
How to fill default values based on column names without typeerror - Pandas
I have a dataframe like as shown below
obs = pd.DataFrame({'person_id' :[1,2,3],'obs_date':['12/31/2007','11/25/2009',np.nan],
'hero_id':[2,4,np.nan],'date':['12/31/2017',np.nan,'10/06/2015'],
…
The Great
- 7,215
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