加载管道仅返回列名

Question

我使用带有自定义类的管道的 joblib 和 tempfile 制作了一个泡菜，当加载序列化管道时，我只得到一个带有功能名称的数组。 这是我第一次为机器学习管道开发自定义类。我不知道 scikit-learn 是否有一个用于数据框选择的类或如何做类似的事情。

# Custom classes
class DataFrameSelector(BaseEstimator, TransformerMixin):
    def __init__(self, attribute_names):
        self.attribute_names = attribute_names
    def fit(self, X, y=None):
        return self
    def transform(self, X):
        return X[self.attribute_names]

class MeanEncoder(BaseEstimator, TransformerMixin):

    def __init__(self):
        return None

    def fit(self, X, y):

        if not isinstance(X, pd.DataFrame):
            if isinstance(X, pd.Series):
                X = pd.DataFrame(X)
            else:
                raise ValueError('Not a pandas DataFrame')

        if X.shape[0] != y.shape[0]:
            raise ValueError('The length of X is different than the length of y')

        df = pd.DataFrame(X.copy())
        df['TARGET'] = y.copy()
        vars_cat = {}

        for col in X.select_dtypes('object').columns:
            ordered_labels = df.groupby(col).agg({'TARGET':'mean'}).sort_values('TARGET', ascending=False).index
            ordinal_labels = {k:i for i, k in enumerate(ordered_labels, 0)}
            vars_cat[col] = ordinal_labels
            df[col] = df[col].map(ordinal_labels)

        self.labels_ = vars_cat
        self.train_cols_ = X.columns

        return self

    def transform(self, X):

        if not isinstance(X, pd.DataFrame):
            if isinstance(X, pd.Series):
                X_transform = pd.DataFrame(X.copy())
            else:
                raise ValueError('Not a pandas DataFrame')

        X_transform = pd.DataFrame(X[self.train_cols_].copy())

        check_array = [col for col in self.labels_.keys() if col not in X_transform.columns and X_transform[col].dtype == object]
        if len(check_array) > 0:
            raise ValueError('Missing the following columns:', check_array)

        for col in self.labels_.keys():
            X_transform[col] = X_transform[col].map(self.labels_[col])

        return X_transform

# --------------------------------------------------------------------

pipeline_grid = Pipeline(steps=[
    ('select_vars', DataFrameSelector(vars),
    ('encoder', MeanEncoder()),
    ('xgboost', xgb.XGBClassifier(random_state=SEED, n_jobs=5, verbosity=2))
])

search = RandomizedSearchCV(
    estimator=pipeline_grid,
    param_distributions=params_dist_grid,
    n_iter=5,
    cv=cv,
    n_jobs=5,
    scoring='roc_auc',
    random_state=SEED,
    verbose=3
)

pipeline_model = search.best_estimator_

s3 = boto3.resource('s3')

# Write
with tempfile.TemporaryFile() as fp:
    joblib.dump(pipeline_modelo, fp)
    fp.seek(0)
    s3.Bucket(NM_BUCKET).put_object(Key= path + name_pipe, Body=fp.read())

# Load
s3 = boto3.client('s3')
with tempfile.TemporaryFile() as fp:
    s3.download_fileobj(Fileobj=fp, Bucket=NM_BUCKET, Key=path + name_pipe)
    fp.seek(0)
    pipe = joblib.load(fp)

结果如下：

array(['VAR01', 'VAR02', 'VAR03', 'VAR04', 'VAR05', 'VAR06', 'VAR07', 'VAR08', 'VAR09', 'VAR10'])

Answer 1

我修复了它从 DataFrameSelector 中删除 BaseEstimator

现在看起来像

class DataFrameSelector(TransformerMixin):
    def __init__(self, attribute_names):
        self.attribute_names = attribute_names
    def fit(self, X, y=None):
        return self
    def transform(self, X):
        return X[self.attribute_names]