1Fsdb::Filter::dbcolmoviUnsgesrtaCtosn(t3r)ibuted Perl DoFcsudmbe:n:tFaitlitoenr::dbcolmovingstats(3)
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NAME

6       dbcolmovingstats - compute moving statistics over a window of a column
7       of data
8

SYNOPSIS

10       dbcolmovingstats [-am] [-w window-width] [-e EmptyValue] column
11

DESCRIPTION

13       Compute moving statistics over a COLUMN of data.  Records containing
14       non-numeric data are considered null do not contribute to the stats
15       (optionally they are treated as zeros with "-a").
16
17       Currently we compute mean and sample standard deviation.  (Note we only
18       compute sample standard deviation, not full population.)  Optionally,
19       with "-m" we also compute median.  (Currently there is no support for
20       generalized quantiles.)
21
22       Values before a sufficient number have been accumulated are given the
23       empty value (if specified with "-e").  If no empty value is given,
24       stats are computed on as many are possible if no empty value is
25       specified.
26
27       Dbcolmovingstats runs in O(1) memory, but must buffer a full window of
28       data.  Quantiles currently will repeatedly sort the window and so may
29       perform poorly with wide windows.
30

OPTIONS

32       -a or --include-non-numeric
33           Compute stats over all records (treat non-numeric records as zero
34           rather than just ignoring them).
35
36       -w or --window WINDOW
37           WINDOW of how many items to accumulate (defaults to 10).  (For
38           compatibility with fsdb-1.x, -n is also supported.)
39
40       -m or --median
41           Show median of the window in addition to mean.
42
43       -e E or --empty E
44           Give value E as the value for empty (null) records.  This null
45           value is then output before a full window is accumulated.
46
47       -f FORMAT or --format FORMAT
48           Specify a printf(3)-style format for output mean and standard
49           deviation.  Defaults to "%.5g".
50
51       Eventually we expect to support other options of dbcolstats.
52
53       This module also supports the standard fsdb options:
54
55       -d  Enable debugging output.
56
57       -i or --input InputSource
58           Read from InputSource, typically a file name, or "-" for standard
59           input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue
60           objects.
61
62       -o or --output OutputDestination
63           Write to OutputDestination, typically a file name, or "-" for
64           standard output, or (if in Perl) a IO::Handle, Fsdb::IO or
65           Fsdb::BoundedQueue objects.
66
67       --autorun or --noautorun
68           By default, programs process automatically, but Fsdb::Filter
69           objects in Perl do not run until you invoke the run() method.  The
70           "--(no)autorun" option controls that behavior within Perl.
71
72       --help
73           Show help.
74
75       --man
76           Show full manual.
77

SAMPLE USAGE

79   Input:
80           #fsdb date  epoch count
81           19980201        886320000       6
82           19980202        886406400       8
83           19980203        886492800       19
84           19980204        886579200       53
85           19980205        886665600       20
86           19980206        886752000       18
87           19980207        886838400       5
88           19980208        886924800       9
89           19980209        887011200       22
90           19980210        887097600       22
91           19980211        887184000       36
92           19980212        887270400       26
93           19980213        887356800       23
94           19980214        887443200       6
95
96   Command:
97           cat data.fsdb | dbmovingstats -e - -w 4 count
98
99   Output:
100               #fsdb date epoch count moving_mean moving_stddev
101               19980201        886320000       6       -       -
102               19980202        886406400       8       -       -
103               19980203        886492800       19      -       -
104               19980204        886579200       53      21.5    21.764
105               19980205        886665600       20      25      19.442
106               19980206        886752000       18      27.5    17.02
107               19980207        886838400       5       24      20.445
108               19980208        886924800       9       13      7.1647
109               19980209        887011200       22      13.5    7.8528
110               19980210        887097600       22      14.5    8.8129
111               19980211        887184000       36      22.25   11.026
112               19980212        887270400       26      26.5    6.6081
113               19980213        887356800       23      26.75   6.3966
114               19980214        887443200       6       22.75   12.473
115               #   | dbcolmovingstats -e - -n 4 count
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SEE ALSO

118       Fsdb.  dbcolstats.  dbmultistats.  dbrowdiff.
119

BUGS

121       Currently there is no support for generalized quantiles.
122

CLASS FUNCTIONS

124   new
125           $filter = new Fsdb::Filter::dbcolmovingstats(@arguments);
126
127       Create a new dbcolmovingstats object, taking command-line arguments.
128
129   set_defaults
130           $filter->set_defaults();
131
132       Internal: set up defaults.
133
134   parse_options
135           $filter->parse_options(@ARGV);
136
137       Internal: parse command-line arguments.
138
139   setup
140           $filter->setup();
141
142       Internal: setup, parse headers.
143
144   run
145           $filter->run();
146
147       Internal: run over each rows.
148

150       Copyright (C) 1991-2018 by John Heidemann <johnh@isi.edu>
151
152       This program is distributed under terms of the GNU general public
153       license, version 2.  See the file COPYING with the distribution for
154       details.
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158perl v5.28.1                      2018-02-17 Fsdb::Filter::dbcolmovingstats(3)
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