def load_sentence_data_frame(sc, dataPath):
df = SQLContext(sc).read.format('com.databricks.spark.csv') \
.options(header='true', inferschema='true') \
.load(dataPath)
# 複製欄位(vector)
df = df.withColumn("_vector", df['vector'])
# 去除_vector的 [ 以及 ]
df = df.select(
df['id'], df['sentence'], df['vector'],
regexp_replace(df['_vector'], "[\]\[]", "").alias("_vector"))
# 分割_vector字串並且轉型
df = df.select(
df['id'], df['sentence'], df['vector'],
split(df['_vector'], " ").cast("array<double>").alias("_vector"))
# 將double轉換為vectory再轉換為numpy array
tmp = df.rdd.flatMap(lambda x: {
Row(x['id'], x['sentence'], x['vector'], Vectors.dense(x['_vector']))
})
# 再轉換為dataframe
df = SQLContext(sc).createDataFrame(tmp)\
.selectExpr("_1 as id",
"_2 as sentence",
"_3 as vector",
"_4 as _vector")
# 回傳dataframe
return df
