我对熊猫索引列的结果感到困惑。
都
db['varname']
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和
db[['varname']]
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给我'varname'的列值。但是,看起来有些细微的差别,因为的输出db['varname']显示了值的类型。
我一直在学习Google的机器学习速成课程,并且他们有一个部分,其中有一个练习教您如何使用pandas和tensorflow。在开始时,他们抓住数据帧,并在紧接着抓住“ total_rooms”和“ median_house_value”系列之后。他们用双括号抓住“ total_rooms”系列,而只用一组括号抓住“ median_house_value”系列。我通读了panda的文档,似乎您需要使用双括号索引到一系列索引中的唯一原因是立即索引2列,即data california_housing_dataframe [[“ median_house_value”,“ total_rooms”]]。
这是我正在谈论的代码。
california_housing_dataframe = pd.read_csv("https://dl.google.com/mlcc/mledu-datasets/california_housing_train.csv", sep=",")
# Define the input feature: total_rooms.
my_feature = california_housing_dataframe[["total_rooms"]]
# Configure a numeric feature column for total_rooms.
feature_columns = [tf.feature_column.numeric_column("total_rooms")]
targets = california_housing_dataframe["median_house_value"]
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如果需要更多上下文,请参见以下更多代码:
california_housing_dataframe = pd.read_csv("https://dl.google.com/mlcc/mledu-datasets/california_housing_train.csv", sep=",")
# Define the input feature: total_rooms.
my_feature = california_housing_dataframe[["total_rooms"]]
# Configure a numeric feature column for total_rooms.
feature_columns = [tf.feature_column.numeric_column("total_rooms")]
targets = california_housing_dataframe["median_house_value"]
def my_input_fn(features, targets, batch_size=1, shuffle=True, num_epochs=None):
"""Trains a linear regression model of one feature.
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