**Fsdb::Filter::dbrowdiff - compute row-by-row differences of some column**

For a given column, compute the differences between each row of the table. Differences are output to two new columns, "absdiff" and "pctdiff". Differences are either relative to the previous column (*incremental* mode), or relative to the first row (...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC**Fsdb::Filter::dbrowcount - count the number of rows in an Fsdb stream**

Count the number of rows and write out a new fsdb file with one column (n) and one value: the number of rows. This program is a strict subset of dbcolstats. Although there are other ways to get a count of rows ("dbcolstats", or "dbrowaccumulate -C 1"...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC**Fsdb::Filter::dbcolstats - compute statistics on a fsdb column**

Compute statistics over a COLUMN of data. Records containing non-numeric data are considered null do not contribute to the stats (with the "-a" option they are treated as zeros). Confidence intervals are a t-test (+/- (t_{a/2})*s/sqrt(n)) and assume ...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC**Fsdb::Filter::dbfilediff - compare two fsdb tables**

Dbfilediff compares two Fsdb tables, row by row. Unlike Unix diff(1), this program assumes the files are identical line-by-line and we compare fields. Thus, insertion of one extra row will result in all subsequent lines being marked different. By def...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC**Fsdb::Filter::dbpipeline - allow db commands to be assembled as pipelines in Perl**

This module makes it easy to create pipelines in Perl using separate processes. (In the past we used to use perl threads.) By default (as with all Fsdb modules), input is from STDIN and output to STDOUT. Two helper functions, fromfile and tofile can ...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC**Fsdb::Filter::dbcolmovingstats - compute moving statistics over a window of a column of data**

Compute moving statistics over a COLUMN of data. Records containing non-numeric data are considered null do not contribute to the stats (optionally they are treated as zeros with "-a"). Currently we compute mean and sample standard deviation. (Note w...

JOHNH/Fsdb-2.69 - 22 Nov 2019 17:43:00 UTC