寻找带字母的数字

Question

我想选择一个DataFrame列，遍历它，只选择数字，并用“Unknow”替换包含字母和其他符号的数字。我尝试了isreal（）方法，但没有成功。有没有办法不用函数就完成这个任务？你知道吗

%matplotlib inline
%pylab inline
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
file = 'C:/Users/Сынкетру/Desktop/attacks.csv'
df = pd.read_csv(file, sep=',', encoding='ISO-8859-1') 


df_clean = df.Age.dropna()

def age(number):
    try:
        number = df.isreal()
    except ValueError:
        number = 'Unknown'

map(age, df_clean)
print(d)

Answer 1

df.Age[~df.Age.apply(np.isreal)] = "unknown"

Answer 2

df = pd.DataFrame(dict(A=['1', 2, '_3', '4.', 'hello', 3.14]))

df['A'] = np.where(pd.to_numeric(df.A, 'coerce').notnull(), df.A, 'unknown')
df