CODEWITHSUNDEEP
pythonpandas
Anthony1199
Anthony1199

Reputation: 21

Add a new element at the end of a Pandas Data Frame

I would like to add of the end of a Pandas Data frame a new row. The problem is that the tofpet_id and tofpet_channel have the same length but they are arrays and not single entries. So I would like to construct new rows, which consists of a single value for tofpet_id and tofpet_channel. For instance we have for row 10 tofpet_id =[1,2] and tofpet_channel=[3,4] and I would like to turn it into two different entries of tofpet_id = 1 and tofpet_channel=3 for the first and tofpet_id = 2 and tofpet_channel=4 for the second. I tried to do it using the code below, actually the temp line. But it doesnt work. Any ideas?

copy_df=df_ecal.copy()

copy_df['entry_id']=np.arange(copy_df.shape[0]) #done

test=df_ecal[df_ecal['n_hits']!=1]

for index,row in test.iterrows():

    for j in range(len(row['tofpet_id'])): #Excellent
        temp = test[row['tofpet_id'][j], row['tofpet_channel'][j], row['entry_id']]
        # copy_df.append(temp,ignore_index=1)
        print(row['tofpet_id'][j])

Upvotes: 0

Views: 817

Answers (1)

Kushim
Kushim

Reputation: 303

EDITED

I miss-read in your case you just need to use the explode function built in pandas e.g.

import pandas as pd

data = {'Name':['Tom', 'Brad', 'Kyle', 'Jerry'],
        'Age':[20, 21, 19, 18],
        'Height' : [6.1, 5.9, 6.0, [6.1, 7.8]]
        }


df = pd.DataFrame(data)
df.explode('Height')

# In your case you can explode with two columns like so:
df.explode(['Age', 'Height'])
# This will take the Nth element of both columns and make a new record.

That will do exactly what you want

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Upvotes: 1

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