如何創建一個函數將數據附加到數據框？

Question

import pandas as pd 
columns_list=['sport','home','away','selection','odds','tipster','stake', 
       'is_won','profit','bookie'] 

df = pd.DataFrame(columns=columns_list) 

def bet(sport,home,away,selection,odds,tipster,stake,profit,bookie): 
    if profit > 0: 
     is_won = True 
    elif profit < 0: 
     is_won = False 
    temp_df = pd.DataFrame([[sport,home,away,selection,odds,tipster,stake, 
          is_won,profit,bookie]], columns=columns_list) 
    df.append(temp_df, ignore_index=True) 
    #print(smemels has been inserted) 
    #add market 

bet(sport="football",home="sporting",away="porto",selection="sporting", 
    odds=2.7,tipster="me",stake=500,profit=500,bookie="marathon") 

我想創建一個空的DataFrame，然後追加新行，通過創建一個函數，所以我只需要把值，它會自動插入。當我運行代碼bet(...)它並不真正追加數據。

Answer 1

，只需加上「全球DF」下面的函數頭和論證就地= true在附加功能：

def bet(sport,home,away,selection,odds,tipster,stake,profit,bookie): 
    global df 
    if profit > 0: 
     is_won = True 
    elif profit < 0: 
     is_won = False 
    temp_df = pd.DataFrame([[sport,home,away,selection,odds,tipster,stake, 
          is_won,profit,bookie]], columns=columns_list) 
    df.append(temp_df, ignore_index=True, inplace = True) 

第一個告訴函數採取全局（函數之外）DF變量，而不是創造的本地一個新的。第二個更改數據框而不是返回一個新對象。

Answer 2

def bet(**kwargs): 
    '''place your code here 

bet(sport="football",home="sporting",away="porto",selection="sporting", 
odds=2.7,tipster="me",stake=500,profit=500,bookie="marathon") 

見http://book.pythontips.com/en/latest/args_and_kwargs.html

kwargs允許你添加keyworded，就像你要怎樣做。