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+--- Thread: How to extract previous and current rows if their value is equal (/thread-11019.html)
How to extract previous and current rows if their value is equal - SriRajesh - Jun-18-2018
Hi,
I want to extract rows if the previous row of Name column equal to 'MM' and current row of Name column is 'MA'
import pandas as pd
import numpy as np
df=pd.DataFrame({'Name':['MM','MA','CS','MM','MM','TH','MM','MA'],'Rank':[1,3,3,1,2,3,2,2],'Score':[120,20,12,15,2,83,22,32]})
for i,(index,row) in enumerate(df.iterrows()):
if i == 0: continue
df[(df.Name.loc[i]=='MA') & (df.Name.loc[i-1]=='MM')]
RE: How to extract previous and current rows if their value is equal - gontajones - Jun-18-2018
df={'Name':["MM","MA","CS","MM","MM","TH","MM","MA"],'Rank':[1,3,3,1,2,3,2,2],'Score':[120,20,12,15,2,83,22,32]}
filtered_df = {'Name': [], 'Rank': [], 'Score': []}
for i in range(len(df['Name'])):
try:
if df['Name'][i] == 'MM' and df['Name'][i+1] == 'MA':
filtered_df['Name'].append(df['Name'][i])
filtered_df['Name'].append(df['Name'][i+1])
filtered_df['Rank'].append(df['Rank'][i])
filtered_df['Rank'].append(df['Rank'][i+1])
filtered_df['Score'].append(df['Score'][i])
filtered_df['Score'].append(df['Score'][i+1])
except:
pass
print(filtered_df)
RE: How to extract previous and current rows if their value is equal - SriRajesh - Jun-18-2018
I still want to put the data in pandas dataframe
RE: How to extract previous and current rows if their value is equal - gontajones - Jun-18-2018
I'm not sure if I understood what you're asking for, maybe this:
import pandas as pd
df=pd.DataFrame({'Name':["MM","MA","CS","MM","MM","TH","MM","MA"],'Rank':[1,3,3,1,2,3,2,2],'Score':[120,20,12,15,2,83,22,32]})
filtered_df = {'Name': [], 'Rank': [], 'Score': []}
for i in range(len(df['Name'])):
try:
if df['Name'][i] == 'MM' and df['Name'][i+1] == 'MA':
filtered_df['Name'].append(df['Name'][i])
filtered_df['Name'].append(df['Name'][i+1])
filtered_df['Rank'].append(df['Rank'][i])
filtered_df['Rank'].append(df['Rank'][i+1])
filtered_df['Score'].append(df['Score'][i])
filtered_df['Score'].append(df['Score'][i+1])
except:
pass
filtered_pd_df = pd.DataFrame(filtered_df)
print(filtered_pd_df)
RE: How to extract previous and current rows if their value is equal - SriRajesh - Jun-18-2018
I used as below:
pd.DataFrame.from_dict(filtered_df),
but your comment also works, Many many thanks
RE: How to extract previous and current rows if their value is equal - volcano63 - Jun-18-2018
(Jun-18-2018, 02:49 PM)SriRajesh Wrote: Hi,
I want to extract rows if the previous row of Name column equal to 'MM' and current row of Name column is 'MA'
import pandas as pd import numpy as np df=pd.DataFrame({'Name':['MM','MA','CS','MM','MM','TH','MM','MA'],'Rank':[1,3,3,1,2,3,2,2],'Score':[120,20,12,15,2,83,22,32]}) for i,(index,row) in enumerate(df.iterrows()): if i == 0: continue df[(df.Name.loc[i]=='MA') & (df.Name.loc[i-1]=='MM')]
Output:print(list(df.iterrows()))
[(0, Name MM
Rank 1
Score 120
Name: 0, dtype: object), (1, Name MA
Rank 3
Score 20
Name: 1, dtype: object), (2, Name CS
Rank 3
Score 12
Name: 2, dtype: object), (3, Name MM
Rank 1
Score 15
Name: 3, dtype: object), (4, Name MM
Rank 2
Score 2
Name: 4, dtype: object), (5, Name TH
Rank 3
Score 83
Name: 5, dtype: object), (6, Name MM
Rank 2
Score 22
Name: 6, dtype: object), (7, Name MA
Rank 2
Score 32
Name: 7, dtype: object)]