mem_compress¶
mem_compress compresses a string which may contain 0-characters.
-
ssCompressed = mem_compress(ssString)
Return Value
ssCompressed is the compressed string. The function inserts an 8 byte long
header at the beginning of the string. The header starts with the 4 characters
gzc\0 followed by a 32-Bit value in little endian byte-order (Intel)
which contains the string length of the uncompressed string.
Parameters
-
ssString ssString is a scalar string.
Example
filename = GetRootDirectory() + "/script/mn_grid.ic";
fp = fopen(filename, "r");
s = fread(fp, "char");
fclose(fp);
c = mem_compress(s);
print "Size uncompressed:", strlen(s);
print "Size compressed:", mem_len(c);
Output:
Size uncompressed:
91099.0000
Size compressed:
17992.0000
Comment
This function uses the zlib-Library (http://www.gzip.org/zlib/). Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler.
UniPlot verwendet Unicode-Strings, die zwei Bytes pro Zeichen verwenden (UTF-16). Die Funktion mem_compress verwendet nur jeweils die unteren Bytes des Unicode-Strings.
Müssen alle Bytes des Unicode-Strings komprimiert werden, können die Funktionen mem_unpack und mem_pack vor dem Komprimieren bzw. nach dem Dekomprimieren verwendet werden:
* mc = mem_compress(mem_unpack("你们好"))
* print mem_pack(mem_uncompress(mc))
你们好
History
| Version | Description |
|---|---|
| 5.0.0 | Unicode strings. |
| 4.2.0 | New |
See also
Overview Strings, File Compression, mem_uncompress, CompressFile, DeCompressFile, mem_pack, mem_unpack
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