遍历 Dataframe 并计算特定值的字数

Question

我有一个 Dataframe 有 2 个这样的列：[短语] [类别] 所以每个短语都有一个特定的类别。 我想做的是遍历 Dataframe 并计算特定类别的所有单词。 因此，例如，可以说类别是新闻。 我想找到所有带有新闻类别的短语并计算总共使用的单词。

我希望有人能帮助我。 我正在使用 Python 和 Pandas。

谢谢

Answer 1

我相信您可以使用groupby function。 例如：

out = df.groupby('category').count()

举个例子：

import pandas as pd
df = pd.DataFrame({'phrase': ["basketball", "football", "tennis", "bread", "honey", "nbc", "cnn", "fox", "bloomberg"],
                  'category': ["sports", "sports", "sports", "food", "food", "news", "news", "news", "news"]})


out = df.groupby('category').count()

print(out)

Output：

          phrase
category        
food           2
news           4
sports         3

Answer 2

你可以这样做：

import pandas as pd
df = pd.DataFrame({
    "Phrases":["Hello, how are you!","I am Good!","Do you want to come over?"],
    "Category":["Question","Answer","Question"]
})
l = {}
for phrase,category in zip(df["Phrases"],df["Category"]):
    try:
        l[category].append(phrase)
    except:
        l[category] = [phrase]
print(l)

出去：

{'Question': ['Hello, how are you!', 'Do you want to come over?'], 'Answer': ['I am Good!']}