如何删除行数据

Question

我的数据框

我想删除同一行数据时col["SALE PRICE"] = '-'

import pandas as pd 
import numpy as np 

sales = pd.read_csv('C:\\Users\\Jerry\\Downloads\\nyc-rolling-sales.csv',sep = ',',encoding = 'latin-1') 

del sales['BOROUGH'] 
del sales['NEIGHBORHOOD'] 
del sales['BLOCK'] 
del sales['ADDRESS'] 
del sales['APARTMENT NUMBER'] 

sales['SALE PRICE'] = np.where(sales['SALE PRICE']=' - ',delimeter, sales['SALE PRICE']) 

语法错误：关键字不能表达

Answer 1

你是在以下行上检查与=而不是==的等同性

sales['SALE PRICE'] = np.where(sales['SALE PRICE']=' - ',delimeter, sales['SALE PRICE']) 

请改为此

sales['SALE PRICE'] = np.where(sales['SALE PRICE']==' - ',delimeter, sales['SALE PRICE']) 

Answer 2

更新：全码

如何：

import pandas as pd 
import numpy as np 

file = 'C:\\Users\\Jerry\\Downloads\\nyc-rolling-sales.csv' 
sales = pd.read_csv(file,sep = ',',encoding = 'latin-1') 

dropcols = ["BOROUGH","NEIGHBORHOOD","BLOCK","ADDRESS","APARTMENT NUMBER"] 
sales = sales.drop(dropcols,axis=1) 

#boolean indexing 
mask = sales['SALE PRICE'] == "-" 
#mask = sales['SALE PRICE'].str.strip() == "-" #use this for spaces 
sales[~mask] 

我不知道你在哪里得到的数据，但你也可以插入一个直接链接：

例如

url = "http://www1.nyc.gov/assets/finance/downloads/pdf/rolling_sales/rollingsales_manhattan.xls" 
sales = pd.read_excel(url,skiprows=4) 

Answer 3

df[df['sales price'] != '-'] 

见 - https://chrisalbon.com/python/pandas_dropping_column_and_rows.html