The FileTools:-Compressed subpackage is a collection of commands for the manipulation of compressed files. These commands support creating, reading from, and writing to compressed files in both the gzip and zip formats.

The data being read or written can consist of strings, binary data (rtables), integers, or floating-point numbers.

In general, a file with a ".zip" extension or a file specification using the notation "subfile" in "zipfile" to denote the zipfile and in-zipfile will be interpreted as a zip archive, while any other extension will be interpreted as gzip format. The Open command accepts a format option to override the examining of the file extension to determine the file format.

Many of these commands accept an option gzipopts. Acceptable values for this option are strings of the form [0-9][fhR]. A digit, if given, sets the compression level. A low value (1) means high speed. A high value (9) means high compression. A level of 0 means no compression. A single letter, if given, sets the compression strategy: the letter f corresponds to filtered data, the letter h corresponds to Huffman-only compression, and the letter R corresponds to run-length encoding. See the zlib Manual for more details.

Zip files also accept the compression level as given by gzipopts, but only support the default compression strategy.

The following is a list of available commands.

The FileTools:-Compressed package was introduced in Maple 16.

For more information on Maple 16 changes, see Updates in Maple 16.

The zip option was introduced in Maple 18.

For more information on Maple 18 changes, see Updates in Maple 18.