Find out the percentage of missing values in each column in the given dataset

Question:

import pandas as pd
df = pd.read_csv('https://query.data.world/s/Hfu_PsEuD1Z_yJHmGaxWTxvkz7W_b0')
percent= 100*(len(df.loc[:,df.isnull().sum(axis=0)>=1 ].index) / len(df.index))
print(round(percent,2))

input is https://query.data.world/s/Hfu_PsEuD1Z_yJHmGaxWTxvkz7W_b0

and the output should be

Ord_id                 0.00
Prod_id                0.00
Ship_id                0.00
Cust_id                0.00
Sales                  0.24
Discount               0.65
Order_Quantity         0.65
Profit                 0.65
Shipping_Cost          0.65
Product_Base_Margin    1.30
dtype: float64
Asked By: Shaswata

||

Answers:

How about this? I think I actually found something similar on here once before, but I’m not seeing it now…

percent_missing = df.isnull().sum() * 100 / len(df)
missing_value_df = pd.DataFrame({'column_name': df.columns,
                                 'percent_missing': percent_missing})

And if you want the missing percentages sorted, follow the above with:

missing_value_df.sort_values('percent_missing', inplace=True)

As mentioned in the comments, you may also be able to get by with just the first line in my code above, i.e.:

percent_missing = df.isnull().sum() * 100 / len(df)
Answered By: Engineero

Update let’s use mean with isnull:

df.isnull().mean() * 100

Output:

Ord_id                 0.000000
Prod_id                0.000000
Ship_id                0.000000
Cust_id                0.000000
Sales                  0.238124
Discount               0.654840
Order_Quantity         0.654840
Profit                 0.654840
Shipping_Cost          0.654840
Product_Base_Margin    1.297774
dtype: float64

IIUC:

df.isnull().sum() / df.shape[0] * 100.00

Output:

Ord_id                 0.000000
Prod_id                0.000000
Ship_id                0.000000
Cust_id                0.000000
Sales                  0.238124
Discount               0.654840
Order_Quantity         0.654840
Profit                 0.654840
Shipping_Cost          0.654840
Product_Base_Margin    1.297774
dtype: float64
Answered By: Scott Boston

To cover all missing values and round the results:

((df.isnull() | df.isna()).sum() * 100 / df.index.size).round(2)

The output:

Out[556]: 
Ord_id                 0.00
Prod_id                0.00
Ship_id                0.00
Cust_id                0.00
Sales                  0.24
Discount               0.65
Order_Quantity         0.65
Profit                 0.65
Shipping_Cost          0.65
Product_Base_Margin    1.30
dtype: float64
Answered By: RomanPerekhrest
import numpy as np
import pandas as pd

raw_data = {'first_name': ['Jason', np.nan, 'Tina', 'Jake', 'Amy'], 
        'last_name': ['Miller', np.nan, np.nan, 'Milner', 'Cooze'], 
        'age': [22, np.nan, 23, 24, 25], 
        'sex': ['m', np.nan, 'f', 'm', 'f'], 
        'Test1_Score': [4, np.nan, 0, 0, 0],
        'Test2_Score': [25, np.nan, np.nan, 0, 0]}
results = pd.DataFrame(raw_data, columns = ['first_name', 'last_name', 'age', 'sex', 'Test1_Score', 'Test2_Score'])


results 

  first_name last_name   age  sex  Test1_Score  Test2_Score
0      Jason    Miller  22.0    m          4.0         25.0
1        NaN       NaN   NaN  NaN          NaN          NaN
2       Tina       NaN  23.0    f          0.0          NaN
3       Jake    Milner  24.0    m          0.0          0.0
4        Amy     Cooze  25.0    f          0.0          0.0

You can use following function, which will give you output in Dataframe

  • Zero Values
  • Missing Values
  • % of Total Values
  • Total Zero Missing Values
  • % Total Zero Missing Values
  • Data Type

Just copy and paste following function and call it by passing your pandas Dataframe

def missing_zero_values_table(df):
        zero_val = (df == 0.00).astype(int).sum(axis=0)
        mis_val = df.isnull().sum()
        mis_val_percent = 100 * df.isnull().sum() / len(df)
        mz_table = pd.concat([zero_val, mis_val, mis_val_percent], axis=1)
        mz_table = mz_table.rename(
        columns = {0 : 'Zero Values', 1 : 'Missing Values', 2 : '% of Total Values'})
        mz_table['Total Zero Missing Values'] = mz_table['Zero Values'] + mz_table['Missing Values']
        mz_table['% Total Zero Missing Values'] = 100 * mz_table['Total Zero Missing Values'] / len(df)
        mz_table['Data Type'] = df.dtypes
        mz_table = mz_table[
            mz_table.iloc[:,1] != 0].sort_values(
        '% of Total Values', ascending=False).round(1)
        print ("Your selected dataframe has " + str(df.shape[1]) + " columns and " + str(df.shape[0]) + " Rows.n"      
            "There are " + str(mz_table.shape[0]) +
              " columns that have missing values.")
#         mz_table.to_excel('D:/sampledata/missing_and_zero_values.xlsx', freeze_panes=(1,0), index = False)
        return mz_table

missing_zero_values_table(results)

Output

Your selected dataframe has 6 columns and 5 Rows.
There are 6 columns that have missing values.

             Zero Values  Missing Values  % of Total Values  Total Zero Missing Values  % Total Zero Missing Values Data Type
last_name              0               2               40.0                          2                         40.0    object
Test2_Score            2               2               40.0                          4                         80.0   float64
first_name             0               1               20.0                          1                         20.0    object
age                    0               1               20.0                          1                         20.0   float64
sex                    0               1               20.0                          1                         20.0    object
Test1_Score            3               1               20.0                          4                         80.0   float64

If you want to keep it simple then you can use following function to get missing values in %

def missing(dff):
    print (round((dff.isnull().sum() * 100/ len(dff)),2).sort_values(ascending=False))


missing(results)

Test2_Score    40.0
last_name      40.0
Test1_Score    20.0
sex            20.0
age            20.0
first_name     20.0
dtype: float64
Answered By: Suhas_Pote

The solution you’re looking for is :

round(df.isnull().mean()*100,2) 

This will round up the percentage upto 2 decimal places

Another way to do this is

round((df.isnull().sum()*100)/len(df),2)

but this is not efficient as using mean() is.

Answered By: Nitish Arora

If there are multiple dataframe below is the function to calculate number of missing value in each column with percentage

def miss_data(df):
    x = ['column_name','missing_data', 'missing_in_percentage']
    missing_data = pd.DataFrame(columns=x)
    columns = df.columns
    for col in columns:
        icolumn_name = col
        imissing_data = df[col].isnull().sum()
        imissing_in_percentage = (df[col].isnull().sum()/df[col].shape[0])*100

        missing_data.loc[len(missing_data)] = [icolumn_name, imissing_data, imissing_in_percentage]
    print(missing_data) 
Answered By: GpandaM

By this following code, you can get the corresponding percentage values from every columns. Just switch the name train_data with df, in case of yours.

Input:

In [1]:

all_data_na = (train_data.isnull().sum() / len(train_data)) * 100
all_data_na = all_data_na.drop(all_data_na[all_data_na == 0].index).sort_values(ascending=False)[:30]
missing_data = pd.DataFrame({'Missing Ratio' :all_data_na})
missing_data.head(20)

Output :

Out[1]: 
                                Missing Ratio
 left_eyebrow_outer_end_x       68.435239
 left_eyebrow_outer_end_y       68.435239
 right_eyebrow_outer_end_y      68.279189
 right_eyebrow_outer_end_x      68.279189
 left_eye_outer_corner_x        67.839410
 left_eye_outer_corner_y        67.839410
 right_eye_inner_corner_x       67.825223
 right_eye_inner_corner_y       67.825223
 right_eye_outer_corner_x       67.825223
 right_eye_outer_corner_y       67.825223
 mouth_left_corner_y            67.811037
 mouth_left_corner_x            67.811037
 left_eyebrow_inner_end_x       67.796851
 left_eyebrow_inner_end_y       67.796851
 right_eyebrow_inner_end_y      67.796851
 mouth_right_corner_x           67.796851
 mouth_right_corner_y           67.796851
 right_eyebrow_inner_end_x      67.796851
 left_eye_inner_corner_x        67.782664
 left_eye_inner_corner_y        67.782664
Answered By: naimur978

For me I did it like that :

def missing_percent(df):
        # Total missing values
        mis_val = df.isnull().sum()
        
        # Percentage of missing values
        mis_percent = 100 * df.isnull().sum() / len(df)
        
        # Make a table with the results
        mis_table = pd.concat([mis_val, mis_percent], axis=1)
        
        # Rename the columns
        mis_columns = mis_table.rename(
        columns = {0 : 'Missing Values', 1 : 'Percent of Total Values'})
        
        # Sort the table by percentage of missing descending
        mis_columns = mis_columns[
            mis_columns.iloc[:,1] != 0].sort_values(
        'Percent of Total Values', ascending=False).round(2)
        
        # Print some summary information
        print ("Your selected dataframe has " + str(df.shape[1]) + " columns.n"      
            "There are " + str(mis_columns.shape[0]) +
              " columns that have missing values.")
        
        # Return the dataframe with missing information
        return mis_columns
Answered By: Salma Elshahawy

Let’s break down your ask

  1. you want the percentage of missing value
  2. it should be sorted in ascending order and the values to be rounded to 2 floating point

Explanation:

  1. dhr[fill_cols].isnull().sum() – gives the total number of missing values column wise
  2. dhr.shape[0] – gives the total number of rows
  3. (dhr[fill_cols].isnull().sum()/dhr.shape[0]) – gives you a series with percentage as values and column names as index
  4. since the output is a series you can round and sort based on the values

code:

(dhr[fill_cols].isnull().sum()/dhr.shape[0]).round(2).sort_values()

Reference:
sort, round

Answered By: Aravind Raju

single line solution

df.isnull().mean().round(4).mul(100).sort_values(ascending=False)
Answered By: bitbang
import numpy as np

import pandas as pd

df = pd.read_csv('https://query.data.world/s/Hfu_PsEuD1Z_yJHmGaxWTxvkz7W_b0')

df.loc[np.isnan(df['Product_Base_Margin']),['Product_Base_Margin']]=df['Product_Base_Margin'].mean()

print(round(100*(df.isnull().sum()/len(df.index)), 2))
Answered By: Malaya Parida

Try this solution


import pandas as pd
df = pd.read_csv('https://query.data.world/s/Hfu_PsEuD1Z_yJHmGaxWTxvkz7W_b0')
print(round(100*(df.isnull().sum()/len(df.index)),2))

Answered By: Sourabh Kulkarni

The best solution I have found – (Only shows the missing columns)

missing_values = [feature for feature in df.columns if df[feature].isnull().sum() > 1]

for feature in missing_values:
  print(f"{feature} {np.round(df[feature].isnull().mean(), 4)}% missing values")
Answered By: Nijaguna Darshan
import pandas as pd
df = pd.read_csv('https://query.data.world/s/Hfu_PsEuD1Z_yJHmGaxWTxvkz7W_b0')
df.isna().sum()

Output:

Ord_id                   0
Prod_id                  0
Ship_id                  0
Cust_id                  0
Sales                   20
Discount                55
Order_Quantity          55
Profit                  55
Shipping_Cost           55
Product_Base_Margin    109
dtype: int64

df.shape

Output: (8399, 10)

# for share [0; 1] of nan in each column

df.isna().sum() / df.shape[0]

Output:

Ord_id                0.0000
Prod_id               0.0000
Ship_id               0.0000
Cust_id               0.0000
Sales                 0.0024  # (20  / 8399)
Discount              0.0065  # (55  / 8399)
Order_Quantity        0.0065  # (55  / 8399)
Profit                0.0065  # (55  / 8399)
Shipping_Cost         0.0065  # (55  / 8399)
Product_Base_Margin   0.0130  # (109 / 8399)
dtype: float64

# for percent [0; 100] of nan in each column

df.isna().sum() / (df.shape[0] / 100)

Output:

Ord_id                0.0000
Prod_id               0.0000
Ship_id               0.0000
Cust_id               0.0000
Sales                 0.2381  # (20  / (8399 / 100))
Discount              0.6548  # (55  / (8399 / 100))
Order_Quantity        0.6548  # (55  / (8399 / 100))
Profit                0.6548  # (55  / (8399 / 100))
Shipping_Cost         0.6548  # (55  / (8399 / 100))
Product_Base_Margin   1.2978  # (109 / (8399 / 100))
dtype: float64

# for share [0; 1] of nan in dataframe

df.isna().sum() / (df.shape[0] * df.shape[1])

Output:

Ord_id                0.0000
Prod_id               0.0000
Ship_id               0.0000
Cust_id               0.0000
Sales                 0.0002  # (20  / (8399 * 10))
Discount              0.0007  # (55  / (8399 * 10))
Order_Quantity        0.0007  # (55  / (8399 * 10))
Profit                0.0007  # (55  / (8399 * 10))
Shipping_Cost         0.0007  # (55  / (8399 * 10))
Product_Base_Margin   0.0013  # (109 / (8399 * 10))
dtype: float64

# for percent [0; 100] of nan in dataframe

df.isna().sum() / ((df.shape[0] * df.shape[1]) / 100)

Output:

Ord_id                0.0000
Prod_id               0.0000
Ship_id               0.0000
Cust_id               0.0000
Sales                 0.0238  # (20  / ((8399 * 10) / 100))
Discount              0.0655  # (55  / ((8399 * 10) / 100))
Order_Quantity        0.0655  # (55  / ((8399 * 10) / 100))
Profit                0.0655  # (55  / ((8399 * 10) / 100))
Shipping_Cost         0.0655  # (55  / ((8399 * 10) / 100))
Product_Base_Margin   0.1298  # (109 / ((8399 * 10) / 100))
dtype: float64
Answered By: Deyvidas B

One-liner

I’m wondering nobody takes advantage of the size and count? It seems the shortest (and probably fastest) way to do it.

df.apply(lambda x: 1-(x.count()/x.size))

Resulting in:

Ord_id                 0.000000
Prod_id                0.000000
Ship_id                0.000000
Cust_id                0.000000
Sales                  0.002381
Discount               0.006548
Order_Quantity         0.006548
Profit                 0.006548
Shipping_Cost          0.006548
Product_Base_Margin    0.012978
dtype: float64

If you find any reason why this is not a good way, please comment

Answered By: tturbo
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