if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 空值統計
res = data.isnull().sum()print(res)================================
PassengerId 0
Survived 0
Pclass 0
Name 0
Sex 0
Age 177
SibSp 0
Parch 0
Ticket 0
Fare 0
Cabin 687
Embarked 2
2 ,Age 列有多少空值 : data[“Age”].isnull().sum()
代碼 :
if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 空值統計
res = data["Age"].isnull().sum()print(res)=========================177
3 ,刪除空值,行 : res = data.dropna()
代碼 :
if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 取出兩列print(data.shape)
res = data.dropna()print(res.shape)=========================(891,12)(183,12)
4 ,刪除空值,列 : res = data.dropna(axis=1)
代碼 :
if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 取出兩列print(data.shape)
res = data.dropna(axis=1)print(res.shape)==================================(891,12)(891,9)
5 ,空值,全部填默認值 :data.fillna(0)
代碼 : 用 0 填充
if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 空值統計
res = data.isnull().sum()print(res)# 空值用 0 補全
data02 = data.fillna(0)# 空值統計
res = data02.isnull().sum()print("=======================================")print(res)===========================================================
PassengerId 0
Survived 0
Pclass 0
Name 0
Sex 0
Age 177
SibSp 0
Parch 0
Ticket 0
Fare 0
Cabin 687
Embarked 2
dtype: int64
=======================================
PassengerId 0
Survived 0
Pclass 0
Name 0
Sex 0
Age 0
SibSp 0
Parch 0
Ticket 0
Fare 0
Cabin 0
Embarked 0
dtype: int64
6 ,空值,指定列填值 :data[“Age”] = data[“Age”].fillna(0)
代碼 :
if __name__ =='__main__':# 讀文件 csv
data = pd.read_csv("titanic_train.csv")# 空值統計
res = data.isnull().sum()print(res)# 空值用 0 補全,指定列
data["Age"]= data["Age"].fillna(0)# 空值統計
res = data.isnull().sum()print("=======================================")print(res)=======================================================
PassengerId 0
Survived 0
Pclass 0
Name 0
Sex 0
Age 177
SibSp 0
Parch 0
Ticket 0
Fare 0
Cabin 687
Embarked 2
dtype: int64
=======================================
PassengerId 0
Survived 0
Pclass 0
Name 0
Sex 0
Age 0
SibSp 0
Parch 0
Ticket 0
Fare 0
Cabin 687
Embarked 2
dtype: int64