python - 如何计算 csv 文件中的行数并忽略未使用的行(使用 python)

Question

我有一个 CSV 文件，其中包含篮球运动员的高度(以英尺和英寸为单位)以及体重。但是，某些数据的脚和高度为 NULL 或空白。

我必须根据体重指数(根据高度和体重计算)得出有多少球员肥胖的结论。

我发现有11名球员是肥胖的。然而，我需要找到数据集中肥胖球员的百分比。我无法弄清楚如何查找玩家总数(忽略那些行中有 NULL 或没有的玩家)。

这是我拥有的数据的示例:

firstname lastname	position firstseason lastseason	h_feet	h_inches weight

Marquis	  Daniels   	G	2003	       2009	     6	       6	  200	
Predrag	 Danilovic	G	1995	       1996	     6	       5	  200
Adrian	  Dantley	F	1976	       1990	     6	       5	  208	
Mike	  Dantoni       G	1975	       1975	     NULL      NULL       NULL
Henry	  Darcey	C	1952	       1952          6	       7	  217	
Jimmy	  Darden	G	1949	       1949	     6	       1	  170	
Oliver	  Darden	F	1967	       1969	     6	       6.5        235	
Yinka	   Dare	        C	1994	       1997	     7	       0	  265	
Jesse	   Dark	        G	1974	       1974	     6	       4.5        210	

您可以看到某些行的数据为 NULL。

到目前为止，这就是我的 python 代码:

def read_csv(filename):
    """
    Reads a Comma Separated Value file,
    returns a list of rows; each row is a dictionary of columns.
    """
    with open(filename, encoding="utf_8_sig") as file:
        reader = csv.DictReader(file)
        rows = list(reader)
    return rows

# Try out the function
players = read_csv("players.csv")

# Print information on the first player, to demonstrate how
# to get to the data
from pprint import pprint


def is_obese(player):
    if (player["h_inches"] and player["h_feet"] and player["weight"]) == 'NULL' or (player["h_inches"] and player["h_feet"] and player["weight"]) == None:
        pass
    else:
        total_h_inches = float(player["h_feet"]) * 12 + float(player["h_inches"])
        bmi = (float(player["weight"])/(total_h_inches**2))* 703
        return bmi >= 30
        
    
count = 0

for player in players:
    if is_obese(player):
         print ('player', player["lastname"], 'is obese')
         count = count + 1
    else:
         pass
print ("The total number of obese players:", count)

它返回:

player Boozer is obese
player Brand is obese
player Catlett is obese
player Davis is obese
player Hamilton is obese
player Lang is obese
player Maxiell is obese
player Miller is obese
player Smith is obese
player Traylor is obese
player White is obese
The total number of obese players: 11

Answer 1

同时保留玩家总数的计数器，并且只有在有数据的情况下才将玩家添加到计数器中。

# returns True only if player has all data, otherwise returns False
def has_data(player):
    return (player["h_inches"] != 'NULL' and
            player["h_feet"]   != 'NULL' and
            player["weight"]   != 'NULL' and
            player["h_inches"] is not None and
            player["h_feet"]   is not None and
            player["weight"]   is not None)

obese_count = 0
total_count = 0

for player in players:
    if has_data(player):
        if is_obese(player):
            print ('player', player["lastname"], 'is obese')
            obese_count += 1
        total_count += 1