1STATIST(1)                  General Commands Manual                 STATIST(1)
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NAME

6       statist  -  calculate Huffman distribution for freeze(1)
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SYNOPSIS

9       statist [ -gx...  ]
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DESCRIPTION

12       The default table is tuned for both C texts and executable files (as in
13       LHARC). If you will freeze any other  files  (natural  language  texts,
14       databases,  images,  fonts,  etc.) you can calculate the matching posi‐
15       tions distribution using the `statist' program,  which  calculates  and
16       displays  the  mentioned  distribution for the given file. It is useful
17       for large (100K or more) files.
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19       Though the built-in  position  table  is  polyvalent,  the  tuning  can
20       increase  the  compression rate up to one additional percent. (Observed
21       mainly on text files.)
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USAGE

24       statist [-g...] < sample_file
25               or
26       gensample | statist [-g...]
27       where `gensample' is a program generating some sample stream  of  bytes
28       similar to files to be frozen.
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30       The  -g  and -x switches have the same meaning as for freeze(1) and may
31       be repeated.
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33       You can also see the intermediate values and  watch  their  changes  by
34       pressing INTR key when you wish.
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36       Note:  If  you  use  gensample | statist , remember that INTR influence
37       BOTH processes !!
38       The results have the following format:
39       n1 n2 n3 n4 n5 n6 n7 n8 (uncertainty = x)
40       Average match length: xx.yy
41       Percentile 99.9: p999
42       Percentile 99.5: p995
43       Percentile 99.0: p990
44       Percentile 97.0: p970
45       Percentile 95.0: p950
46       Percentile 90.0: p900
47       Percentile 80.0: p800
48       Percentile 70.0: p700
49       Percentile 50.0: p500
50       Sigma: xx.yy
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52       Here n1 - n8 are values of  the  calculated  position  table  elements,
53       uncertainty  is  a number which denotes validity of given results (non-
54       zero values of uncertainty indicate that the results may be  unusable).
55       Other  values  (average  match  length,  percentiles and sigma) are FYI
56       only.
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58       You  may  create  the  /etc/default/freeze  file  (if  you  don't  like
59       /etc/default/ directory, choose another - in MS-DOS it is FREEZE.CNF in
60       the directory of FREEZE.EXE), which has the following format:
61               name = n1 n2 n3 n4 n5 n6 n7 n8
62       (name must start in column 1). For example:
63       ---------- cut here -----------
64       # This is freeze's defaults file
65       russian=0 0 1 2 6 20 31 2   # The sample was mailx.lp (Russian)
66       english=0 0 1 2 7 16 36 0   # The sample was gcc.lp (English)
67       # End of file
68       ---------- cut here -----------
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70       If you find values, which are better THAN DEFAULT both for text (C pro‐
71       grams) and binary (executable) files, please send them to me.
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73       Important  note:  statist.c  is  NOT a part of freeze package, it is an
74       aditional feature.
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SEE ALSO

78       freeze(1), melt(1), fcat(1)
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DIAGNOSTICS

81       Huffman tree has more than 8 levels, reducing...
82               Self-explanatory, but sometimes reducing  falls  into  infinite
83               loop.
84       xxxK
85               Progress  indicator  is  written  after  each 4K of a file pro‐
86               cessed.
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BUGS

89       Sometimes use of the results with uncertainty = 1  (on  a  file)  gives
90       compression  rate worse than default but use of the results with uncer‐
91       tainty = 13 (on other file) works quite good.
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93       Found  bugs  descriptions,  incompatibilities,  etc.   please  send  to
94       leo@s514.ipmce.su.
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99                                     local                          STATIST(1)
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