Drop ALL rows in pandas until a specific string is found then stop dropping

user_16244395 0
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I have a dataframe and I want to delete every row until a specific string is found.

I have tried a couple things but nothing seems to be working. Here is what I have tried:

df[((df.Plate != 'Group Summaries'))]
df.loc[: df[(df['Plate:'] == 'Group Summaries')].index[0], :]
df[(df['Plate:'] == "Group Summaries").idxmax():]
pandas python
2 Answers

Why don't you find the first index where this case appears and then delete all previous row?

import pandas as pd

# Data
df = pd.DataFrame(
    {"Plate": ["a", "b", "a", "c", "a", "c", "c"]})

# First index where values is c
idx = df.index[df["Plate"].eq("c")].min()

# Drop previous rows
df = df[idx:]
user_48193760

You can use:

df[df['Plate'].eq('Group Summaries').cummax()]

How it works:

  • mark True the rows with "Group Summaries" in the "Plate" column
  • forward the True to all next rows with cummax
  • use boolean indexing to select the rows
user_163434640
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