在python的for回圈中繞過ValueError

def decade_total_count(decade, name):
    """
    sums up the number of births of the given 
    female baby `name` in a 10-year period
    
    Parameters:
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    decade ... starting year of the decade
    name   ... female name 
           ... str
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    """
    count = 0
    
    for i in range(decade, decade 10):
        yearly = females[(females['name']==name) & (females['year']==i)]['births'].item()
        count = count   yearly
        
    return count

我正在嘗試使用上面的函式來獲取資料中任何名稱的出生次數，但是只要有一年沒有出現該名稱，我的回圈就會停止。在這種情況下，我會收到此值錯誤：

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
/var/folders/yf/s14dt13x11n82t5kg4260v800000gn/T/ipykernel_4325/1603862037.py in <module>
----> 1 total_count('Jennifer')

/var/folders/yf/s14dt13x11n82t5kg4260v800000gn/T/ipykernel_4325/1143784105.py in total_count(name)
     42 
     43     for i in range(start, end, 10):
---> 44         counts.append(decade_total_count(i, name))
     45 
     46     return counts

/var/folders/yf/s14dt13x11n82t5kg4260v800000gn/T/ipykernel_4325/1143784105.py in decade_total_count(decade, name)
     15 
     16     for i in range(decade, decade 10):
---> 17         yearly = females[(females['name']==name) & (females['year']==i)]['births'].item()
     18         count = count   yearly
     19 

~/Desktop/anaconda3/lib/python3.9/site-packages/pandas/core/base.py in item(self)
    329         if len(self) == 1:
    330             return next(iter(self))
--> 331         raise ValueError("can only convert an array of size 1 to a Python scalar")
    332 
    333     @property

ValueError: can only convert an array of size 1 to a Python scalar

我怎樣才能繞過錯誤并讓我的回圈在我的資料中不包含給定“名稱”的情況下持續多年？我弄亂了try, except,else和finally子句，但不知何故，它打破了我的回圈，只回傳 0。

uj5u.com熱心網友回復：

抱歉，我沒有關于變數的足夠資訊female。

嘗試這個：

def decade_total_count(decade, name):
    """
    sums up the number of births of the given 
    female baby `name` in a 10-year period
    
    Parameters:
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    decade ... starting year of the decade
    name   ... female name 
           ... str
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    """
    count = 0
    
    for i in range(decade, decade 10):
        try:
            yearly = females[(females['name']==name) & (females['year']==i)]['births'].item()
        except ValueError:
            continue
        count = count   yearly
        
    return count

如果 aValueError被提出，只需抓住它并運行下一次迭代。

uj5u.com熱心網友回復：

你還沒有展示你嘗試過的東西，所以我不知道你到底哪里出錯了。但是，在回圈中放置一個 try-except 塊應該可以解決問題：

def decade_total_count(decade, name):
    """
    sums up the number of births of the given 
    female baby `name` in a 10-year period
    
    Parameters:
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    decade ... starting year of the decade
    name   ... female name 
           ... str
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    """
    count = 0
    
    for i in range(decade, decade 10):
        try:
            yearly = females[(females['name']==name) & (females['year']==i)]['births'].item()
            count = count   yearly
        except ValueError as e:
            print(f"Encountered error: {e}. Skipping.")
        
    return count

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