PANDAS find exact given string/word from a column

问题

So, I have a pandas column name Notes which contains a sentence or explanation of some event. I am trying find some given words from that column and when I find that word I am adding that to the next column as Type

The problem is for some specific word for example Liar, Lies its picking up word like familiar and families because they both have liar and lies in them.

Notes                                  Type
2 families are living in the address   Lies
He is a liar                           Liar
We are not familiar with this          Liar

As you can see from above only the second sentence is correct. How do I only pick up separate word like liar, lies and not families or familiar.

This was my approach,

word= ["Lies"]

for i in range(0, len(df)):
    for f in word:
        if f in df["Notes"][i]:
            df["Type"][i] = "Lies"

Appreciate any help. Thanks

回答1:

Use \b for word boundary in regex, and .str.extract to find pattern:

 df.Notes.str.extract(r'\b(lies|liar)\b')

To label those rows containing that word, do:

df['Type'] = np.where(df.Notes.str.contains(r'\b(lies|liar)\b'), 'Lies', 'Not Lies')

回答2:

Well I agree with Quang Hoang answer. Please make sure you are aware about sentences like "He is not a liar". Where it will still match and give you Liar.

回答3:

I think this piece if code will work fine for you!

import pandas as pd

df = pd.DataFrame.from_dict({"Notes":["2 families are living in the address"  ,
"He is a liar  "              ,           
"We are not familiar with this "   ]  }) 



word= ["liar","are","this"]
found_in_whole_string =[]

for i in range(0, len(df)):
    found_one_word=[]
    for f in word:
        if f in df["Notes"][i].split(" "):
            found_one_word.append(f)
        else:
            found_one_word.append("")
    found_in_whole_string.append(",".join([word for word in found_one_word if len(word) > 0])  )

df["type"] = found_in_whole_string

来源：https://stackoverflow.com/questions/62432059/pandas-find-exact-given-string-word-from-a-column

标签

python

pandas

text-mining