Python 尝试忽略csv文件中的Nan会引发类型错误

我正在加载一个包含数据的本地csv文件。我试图找到一行中混合了NaN和数字的最小浮点数。
我尝试使用名为np.nanmin的numpy函数，但它抛出：

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“TypeError:”尝试将列转换为float显式地揭示了问题，您的“5000+”没有转换为“float64”

coun_weight['Launch Mass (Kilograms)'].astype('float64')

结果:

    ValueError: invalid literal for float(): 5,000+

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我尝试测试它，所有有问题的值都是：

coun_weight = pd.read_csv('database.csv')

print (coun_weight.loc[pd.to_numeric(coun_weight['Launch Mass (Kilograms)'], errors='coerce').isnull(), 'Launch Mass (Kilograms)'].dropna())
1091    5,000+
1092    5,000+
1093    5,000+
1094    5,000+
1096    5,000+
Name: Launch Mass (Kilograms), dtype: object

解决办法是：

coun_weight['Launch Mass (Kilograms)'] = 
coun_weight['Launch Mass (Kilograms)'].replace('5,000+', 5000).astype(float)

print (coun_weight['Launch Mass (Kilograms)'].iloc[1091:1098])
1091    5000.0
1092    5000.0
1093    5000.0
1094    5000.0
1095       NaN
1096    5000.0
1097    6500.0
Name: Launch Mass (Kilograms), dtype: float64

然后，如果需要使用

NaN

s-查找最小值，其中跳过

NaN

s：

print (coun_weight['Launch Mass (Kilograms)'].min())
0.0

测试某些

0

是否在列中：

a = coun_weight['Launch Mass (Kilograms)']
print (a[a == 0])
912    0.0
Name: Launch Mass (Kilograms), dtype: float64

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另一种可能的解决方案是将此值替换为

NaN

s：

coun_weight['Launch Mass (Kilograms)'] = 
pd.to_numeric(coun_weight['Launch Mass (Kilograms)'], errors='coerce')

print (coun_weight['Launch Mass (Kilograms)'].iloc[1091:1098])
1091       NaN
1092       NaN
1093       NaN
1094       NaN
1095       NaN
1096       NaN
1097    6500.0
Name: Launch Mass (Kilograms), dtype: float64

---

在CSV FLICAN中，你的CSV文件中有一些空的字段，这些值看起来是空的字段？HES是一个链接到整个CSV文件：空白空间是我的权重内的Na值。例如1390中国Na谢谢帮助！你为我突出了这个问题：

a = coun_weight['Launch Mass (Kilograms)']
print (a[a == 0])
912    0.0
Name: Launch Mass (Kilograms), dtype: float64

coun_weight['Launch Mass (Kilograms)'] = 
pd.to_numeric(coun_weight['Launch Mass (Kilograms)'], errors='coerce')

print (coun_weight['Launch Mass (Kilograms)'].iloc[1091:1098])
1091       NaN
1092       NaN
1093       NaN
1094       NaN
1095       NaN
1096       NaN
1097    6500.0
Name: Launch Mass (Kilograms), dtype: float64