DataFrame.to_hdf()

DataFrame.to_hdf(path_or_buf, key, **kwargs) [source]

Write the contained data to an HDF5 file using HDFStore.

Parameters:

path_or_buf : the path (string) or HDFStore object key : string indentifier for the group in the store mode : optional, {?a?, ?w?, ?r+?}, default ?a? 'w' Write; a new file is created (an existing file with the same name would be deleted). 'a' Append; an existing file is opened for reading and writing, and if the file does not exist it is created. 'r+' It is similar to 'a', but the file must already exist. format : ?fixed(f)|table(t)?, default is ?fixed? fixed(f) : Fixed format

Fast writing/reading. Not-appendable, nor searchable

table(t)

: Table format

Write as a PyTables Table structure which may perform worse but allow more flexible operations like searching / selecting subsets of the data

append : boolean, default False

For Table formats, append the input data to the existing

data_columns : list of columns, or True, default None

List of columns to create as indexed data columns for on-disk queries, or True to use all columns. By default only the axes of the object are indexed. See here.

Applicable only to format=?table?.

complevel : int, 1-9, default 0

If a complib is specified compression will be applied where possible

complib : {?zlib?, ?bzip2?, ?lzo?, ?blosc?, None}, default None

If complevel is > 0 apply compression to objects written in the store wherever possible

fletcher32 : bool, default False

If applying compression use the fletcher32 checksum

dropna : boolean, default False.

If true, ALL nan rows will not be written to store.