我的gzip
约为90 GB。这完全在磁盘空间内,但远大于RAM。
如何将其导入到pandas数据框中?我在命令行中尝试了以下内容:
# start with Python 3.4.5
import pandas as pd
filename = 'filename.gzip' # size 90 GB
df = read_table(filename, compression='gzip')
然而,几分钟后,Python以Kill 9
关闭。
定义数据库对象df
后,我打算将其保存到HDF5中。
这样做的正确方法是什么?如何使用pandas.read_table()
执行此操作?
答案 0 :(得分:9)
我这样做:
filename = 'filename.gzip' # size 90 GB
hdf_fn = 'result.h5'
hdf_key = 'my_huge_df'
cols = ['colA','colB','colC','ColZ'] # put here a list of all your columns
cols_to_index = ['colA','colZ'] # put here the list of YOUR columns, that you want to index
chunksize = 10**6 # you may want to adjust it ...
store = pd.HDFStore(hdf_fn)
for chunk in pd.read_table(filename, compression='gzip', header=None, names=cols, chunksize=chunksize):
# don't index data columns in each iteration - we'll do it later
store.append(hdf_key, chunk, data_columns=cols_to_index, index=False)
# index data columns in HDFStore
store.create_table_index(hdf_key, columns=cols_to_index, optlevel=9, kind='full')
store.close()