1DBFILEDIFF(1)         User Contributed Perl Documentation        DBFILEDIFF(1)
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NAME

6       dbfilediff - compare two fsdb tables
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SYNOPSIS

9           dbfilediff [-Eq] [-N diff_column_name] --input table1.fsdb --input table2.fsdb
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11       OR
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13           cat table1.fsdb  | dbfilediff [-sq] --input table2.fsdb
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DESCRIPTION

16       Dbfilediff compares two Fsdb tables, row by row.  Unlike Unix diff(1),
17       this program assumes the files are identical line-by-line and we
18       compare fields.  Thus, insertion of one extra row will result in all
19       subsequent lines being marked different.
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21       By default, all columns must be unique.  (At some point, support to
22       specific specific columns may be added.)
23
24       Output is a new table with a new column "diff" (or something else if
25       the "-N" option is given), "-"  and "+" for the first and second non-
26       equal rows, "=" for matching lines, or "~" if they are equal with
27       epsilon numerics (in which case only the second row is included).
28       Unlike Unix diff(1), we output all rows (the "=" lines), not just diffs
29       (the "--quiet" option suppresses this output).
30
31       Optionally, with "-E" it will do a "epsilon numeric" comparision, to
32       account for things like variations in different computer's floating
33       point precision and differences in printf output.
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35       Epsilon comparision is asymmetric, in that it assumes the first input
36       is correct an allows the second input to vary, but not the reverse.
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38       Because two tables are required, input is typically in files.  Standard
39       input is accessible by the file "-".
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OPTIONS

42       -E or --epsilon
43           Do epsilon-numeric comparison. (Described above.)
44
45           Epsilon-comparision is only done on columns that look like floating
46           point numbers, not on strings or integers.  Epsilon comparision
47           allows the last digit to vary by 1, or for there to be one extra
48           digit of precision, but only for floating point numbers.
49
50           Rows that are within epsilon are not considered different for
51           purposes of the exit code.
52
53       --exit
54           Exit with a status of 1 if some differences were found.  (By
55           default, the exit status is 0 with or without differences if the
56           file is processed successfully.)
57
58       -N on --new-name
59           Specify the name of the "diff" column, if any.  (Default is
60           "diff".)
61
62       -q or --quiet
63           Be quiet, suppressing output for identical rows.  (This behavior is
64           different from Unix diff(1) where "-q" suppresses all output.)  If
65           repeated, omits epsilon-equivalent rows.
66
67       This module also supports the standard fsdb options:
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69       -d  Enable debugging output.
70
71       -i or --input InputSource
72           Read from InputSource, typically a file name, or "-" for standard
73           input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue
74           objects.
75
76       -o or --output OutputDestination
77           Write to OutputDestination, typically a file name, or "-" for
78           standard output, or (if in Perl) a IO::Handle, Fsdb::IO or
79           Fsdb::BoundedQueue objects.
80
81       --autorun or --noautorun
82           By default, programs process automatically, but Fsdb::Filter
83           objects in Perl do not run until you invoke the run() method.  The
84           "--(no)autorun" option controls that behavior within Perl.
85
86       --help
87           Show help.
88
89       --man
90           Show full manual.
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SAMPLE USAGE

93   Input:
94           #fsdb event clock absdiff pctdiff
95           _null_getpage+128   815812813.281756        0       0
96           _null_getpage+128   815812813.328709        0.046953        5.7554e-09
97           _null_getpage+128   815812813.353830        0.025121        3.0793e-09
98           _null_getpage+128   815812813.357169        0.0033391       4.0929e-10
99
100       And in the file TEST/dbfilediff_ex.in-2:
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102           #fsdb event clock absdiff pctdiff
103           _null_getpage+128   815812813.281756        0       0
104           _null_getpage+128   815812813.328709        0.046953        5.7554e-09
105           _null_getpage+128   815812813.353830        0.025121        3.0793e-09
106           _null_getpage+128   815812813.357169        0.003339        4.0929e-10
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108   Command:
109           cat TEST/dbfilediff_ex.in | dbfilediff -i - -i TEST/dbfilediff_ex.in-2
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111   Output:
112           #fsdb event clock absdiff pctdiff diff
113           _null_getpage+128   815812813.281756        0       0       =
114           _null_getpage+128   815812813.328709        0.046953        5.7554e-09      =
115           _null_getpage+128   815812813.353830        0.025121        3.0793e-09      =
116           _null_getpage+128   815812813.357169        0.0033391       4.0929e-10      -
117           _null_getpage+128   815812813.357169        0.003339        4.0929e-10      +
118           #   | dbfilediff --input TEST/dbfilediff_ex.in-2
119
120       By comparision, if one adds the "-s" option, then all rows will pass as
121       equal.
122

SEE ALSO

124       Fsdb.  dbrowuniq.  dbfilediff.
125
126       dbrowdiff, dbrowuniq, and dbfilediff are similar but different.
127       dbrowdiff computes row-by-row differences for a column, dbrowuniq
128       eliminates rows that have no differences, and dbfilediff compares
129       fields of two files.
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132       Copyright (C) 2012-2018 by John Heidemann <johnh@isi.edu>
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134       This program is distributed under terms of the GNU general public
135       license, version 2.  See the file COPYING with the distribution for
136       details.
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140perl v5.38.0                      2023-07-20                     DBFILEDIFF(1)
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