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format = one of bzip2, gzip, zip, or zlib

This option allows a compression format to be specified explicitly. Options are bzip2 , gzip , zip , or zlib . The default is zlib.

The Compress(A) command takes the given byte array or list and compresses it into a lossless, more compact format. The return value is a ByteArray.

If A is a list, its contents must be integers between -128 and 127.

$\mathrm{OmegaArray}≔\mathrm{Array}\left(1..{10}^5\,\mathrm{NumberTheory}:-\mathrm{NumberOfPrimeFactors}\,\mathrm{datatype}=\mathrm{integer}\left[1\right]\right)$

$\mathrm{CompressedOmegaArray}≔\mathrm{ArrayTools}:-\mathrm{Compress}\left(\mathrm{OmegaArray}\right)$

$\mathrm{numelems}\left(\mathrm{OmegaArray}\right),\mathrm{numelems}\left(\mathrm{CompressedOmegaArray}\right)$

$100000,37013$

$\mathrm{data}≔\mathrm{Statistics}:-\mathrm{Sample}\left(\mathrm{DiscreteUniform}\left(-10\,10\right)\,1000000\right)$

$\mathrm{original}≔\mathrm{convert}\left(\mathrm{data}\,\mathrm{ByteArray}\right)$

$\mathrm{compressed}≔\mathrm{ArrayTools}:-\mathrm{Compress}\left(\mathrm{original}\right)$

$1.-\frac{\mathrm{numelems}\left(\mathrm{compressed}\right)}{\mathrm{numelems}\left(\mathrm{original}\right)}$

$0.8718235000$

$\mathrm{PaulCliffordText}≔''It\; was\; a\; dark\; and\; stormy\; night;\; the\; rain\; fell\; in\; torrents\; -\; except\; at\; occasional\; intervals,\; when\; it\; was\; checked\; by\; a\; violent\; gust\; of\; wind\; which\; swept\; up\; the\; streets\; (for\; it\; is\; in\; London\; that\; our\; scene\; lies),\; rattling\; along\; the\; housetops,\; and\; fiercely\; agitating\; the\; scanty\; flame\; of\; the\; lamps\; that\; struggled\; against\; the\; darkness.''\:$

$\mathrm{original}≔\mathrm{StringTools}:-\mathrm{ToByteArray}\left(\mathrm{PaulCliffordText}\right)$

$\mathrm{compressed}≔\mathrm{ArrayTools}:-\mathrm{Compress}\left(\mathrm{original}\,\mathrm{format}=\mathrm{gzip}\right)$

$1.-\frac{\mathrm{numelems}\left(\mathrm{compressed}\right)}{\mathrm{numelems}\left(\mathrm{original}\right)}$

$0.2996941896$

The ArrayTools[Compress] command was introduced in Maple 2015.

For more information on Maple 2015 changes, see Updates in Maple 2015 .

The ArrayTools[Compress] command was updated in Maple 2018.

The format option was updated in Maple 2018.