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NAME

recs-collate

recs-collate --help-all

Help from: --help-aggregators:
array: collect values from provided field into an array
average, avg: averages provided field
cb, countby: counts by unique value for a field
concat, concatenate: concatenate values from provided field
corr, correl, correlation: find correlation of provided fields
count, ct: counts (non-unique) records
cov, covar, covariance: find covariance of provided fields
dcount, dct, distinctcount, distinctct: count unique values from provided field
first: first value for a field
firstrec, firstrecord: first record
last: last value for a field
lastrec, lastrecord: last record seen
linearregression, linreg: perform a linear regression of provided fields, dumping various statistics
max, maximum: maximum value for a field
min, minimum: minimum value for a field
mode: most common value for a field
perc, percentile: value of pXX for field
percentilemap, percmap: map of percentile values for field
recformax, recformaximum, recordformax, recordformaximum: returns the record corresponding to the maximum value for a field
recformin, recforminimum, recordformin, recordforminimum: returns the record corresponding to the minimum value for a field
records, recs: returns an arrayref of all records
stddev: find standard deviation of provided field
sum: sums provided field
uarray: collect unique values from provided field into an array
uconcat, uconcatenate: concatenate unique values from provided field
valuestokeys, vk: use one key-value as a key for a different value in the record
var, variance: find variance of provided field

Help from: --help-basic:
Usage: recs-collate <args> [<files>]
   Take records, grouped togther by --keys, and compute statistics (like
   average, count, sum, concat, etc) within those groups.

   For starting with collate, try doing single --key collates with some number
   of aggregators (list available in --list-agrregators)

Arguments:
   --dlaggregator|-A ...                         Specify a domain language
                                                 aggregate. See "Domain Language
                                                 Integration" below.
   --aggregator|-a <aggregators>                 Colon separated list of
                                                 aggregate field specifiers. See
                                                 "Aggregates" section below.
   --mr-agg <name> <map> <reduce> <squish>       Specify a map reduce
                                                 aggregator via 3 snippets,
                                                 similar to mr_agg() from the
                                                 domain language.
   --ii-agg <name> <initial> <combine> <squish>  Specify an inject into
                                                 aggregator via 3 snippets,
                                                 similar to ii_agg() from the
                                                 domain language.
   --incremental                                 Output a record every time an
                                                 input record is added to a
                                                 clump (instead of every time a
                                                 clump is flushed).
   --[no]-bucket                                 With --bucket outputs one
                                                 record per clump, with --no-
                                                 bucket outputs one record for
                                                 each record that went into
                                                 the clump.
   --key|-k <keys>                               Comma separated list of key
                                                 fields. May be a key spec or
                                                 key group
   --dlkey|-K ...                                Specify a domain language key.
                                                 See "Domain Language
                                                 Integration" section in --help-
                                                 more.
   --size|--sz|-n <number>                       Number of running clumps to
                                                 keep.
   --adjacent|-1                                 Only group together adjacent
                                                 records. Avoids spooling
                                                 records into memeory
   --cube                                        See "Cubing" section in --help-
                                                 more.
   --clumper ...                                 Use this clumper to group
                                                 records. May be specified
                                                 multiple times. See --help-
                                                 clumping.
   --dlclumper ...                               Use this domain language
                                                 clumper to group records. May
                                                 be specified multiple times.
                                                 See --help-clumping.
   --list-aggregators|--list                     Bail and output a list of
                                                 aggregators
   --show-aggregator <aggregator>                Bail and output this
                                                 aggregator's detailed usage.
   --list-clumpers                               Bail and output a list of
                                                 clumpers
   --show-clumper <clumper>                      Bail and output this clumper's
                                                 detailed usage.
   --filename-key|fk <keyspec>                   Add a key with the source
                                                 filename (if no filename is
                                                 applicable will put NONE)

  Help Options:
      --help-aggregators     List the aggregators
      --help-all             Output all help for this script
      --help                 This help screen
      --help-clumping        Help on clumping; mechanisms to group records
                             across a stream
      --help-domainlanguage  Help on the recs domain language, a [very
                             complicated] way of specifying valuations (which
                             act like keys) or aggregators
      --help-keygroups       Help on keygroups, a way of specifying
                             multiple keys
      --help-keys            Help on keygroups and keyspecs
      --help-keyspecs        Help on keyspecs, a way to index deeply and
                             with regexes
      --help-more            Larger help documentation

Examples:
   Count clumps of adjacent lines with matching x fields.
      recs-collate --adjacent --key x --aggregator count
   Count number of each x field value in the entire file.
      recs-collate --key x --aggregator count
   Finds the maximum latency for each date, hour pair
      recs-collate --key date,hour --aggregator worst_latency=max,latency
   Find the median value of x+y in records
      recs-collate --dlaggregator "m=perc(50,snip(<<{{x}}+{{y}}>>))"

Help from: --help-clumping:
CLUMPING:
   "Clumping" defines a way of taking a stream of input records and rearranging
   them into to groups for consideration. The most common "consideration" for
   such a group of records is the application of one or more aggregators by recs-
   collate and the most common clumpers are those specifiable by recs-collate's
   normal options. However, other recs scripts can use "clumpers" and much more
   complex clumping is possible. A list of clumpers can be found via the --list-
   clumpers option on recs-collate and documentation for individual clumpers can
   be inspected via --show-clumper.

Examples:
   Group adjacent records for each host and output each such group's size.
      recs-collate -c keylru,host,1 -a ct
   Output the successive differences of the time field.
      recs-collate -c window,2 --dla 'time_delta=xform(recs, <<{{#1/time}} - {{#0/time}}>>)'

Full list:
   cubekeyperfect: clump records by the value for a key, additionally cubing them
   keylru: clump records by the value for a key, limiting number of active clumps
   keyperfect: clump records by the value for a key
   window: clump records by a rolling window

Help from: --help-domainlanguage:
DOMAIN LANGUAGE
   The normal mechanism for specifying keys and aggregators allows one to
   concisely instantiate the objects that back them in the platform and is
   certainly the easiest way to use recs. The record stream domain language
   allows the creation of these objects in a programmatic way, with neither the
   syntactic issues of the normal way nor its guiding hand.

   The domain language is itself just Perl with a collection of library
   functions for creating platform objects included. Your favorite aggregators
   are all here with constructors matching their normal token. For convenience
   of e.g. last, aggregators are also included with a prefixed underscore.

   Below you can find documentation on all the "built in" functions. Most
   aggregators and deaggregators should be present with arguments comparable to
   their normal instantiation arugments, but with keyspec parameters replaced
   with valuations parameters.

Special Syntax
   Where one sees a <snippet> argument below, a string scalar is expected,
   however quoting these can get fairly difficult and they can be confused with
   non-<snippet> scalars.

   Example:
     --dla "silly= uconcat(',', snip('{{x}} * 2'))"

   To remedy this, one may use <<CODE>> to inline a snippet which will be
   immediately understood by the typing mechanism as being code. Escaping inside
   this is as single quotes in Perl.

   Example With <<CODE>>
     --dla 'silly= uconcat(",", <<{{x}} * 2>>)'

   Furthermore one may mark variables to be propagated in by prefixing CODE like
   <<var1,var2,var3|CODE>>:
     --dla 'silly= $f=2; uconcat(",", <<f|{{x}} * $f>>)'

Function Library
   ii_agg(<snippet>, <snippet>[, <snippet>])
   ii_aggregator(<snippet>, <snippet>[, <snippet>])
   inject_into_agg(<snippet>, <snippet>[, <snippet>])
   inject_into_aggregator(<snippet>, <snippet>[, <snippet>])
      Take an initial snippet, a combine snippet, and an optional squish snippet
      to produce an ad-hoc aggregator based on inject into. The initial snippet
      produces the aggregate value for an empty collection, then combine takes
      $a representing the aggregate value so far and $r representing the next
      record to add and returns the new aggregate value. Finally, the squish
      snippet takes $a representing the final aggregate value so far and
      produces the final answer for the aggregator.

      Example(s):
         Track count and sum to produce average:
            ii_agg(<<[0, 0]>>, <<[$a->[0] + 1, $a->[1] + {{ct}}]>>, <<$a->[1] / $a->[0]>>)

   for_field(qr/.../, <snippet>)
      Takes a regex and a snippet of code. Creates an aggregator that creates a
      map. Keys in the map correspond to fields chosen by matching the regex
      against the fields from input records. Values in the map are produced by
      aggregators which the snippet must act as a factory for ($f is the field).

      Example(s):
         To aggregate the sums of all the fields beginning with "t"
            for_field(qr/^t/, <<sum($f)>>)

   for_field(qr/.../, qr/.../, <snippet>)
      Takes two regexes and a snippet of code. Creates an aggregator that
      creates a map. Keys in the map correspond to pairs of fields chosen by
      matching the regexes against the fields from input records. Values in the
      map are produced by aggregators which the snippet must act as a factory
      for ($f1 is the first field, $f2 is the second field).

      Example(s):
         To find the covariance of all x-named fields with all y-named fields:
            for_field(qr/^x/, qr/^y/, <<covar($f1, $f2)>>)

   map_reduce_agg(<snippet>, <snippet>[, <snippet>])
   map_reduce_aggregator(<snippet>, <snippet>[, <snippet>])
   mr_agg(<snippet>, <snippet>[, <snippet>])
   mr_aggregator(<snippet>, <snippet>[, <snippet>])
      Take a map snippet, a reduce snippet, and an optional squish snippet to
      produce an ad-hoc aggregator based on map reduce. The map snippet takes $r
      representing a record and returns its mapped value. The reduce snippet
      takes $a and $b representing two mapped values and combines them. Finally,
      the squish snippet takes a mapped value $a representing all the records
      and produces the final answer for the aggregator.

      Example(s):
         Track count and sum to produce average:
            mr_agg(<<[1, {{ct}}]>>, <<[$a->[0] + $b->[0], $a->[1] + $b->[1]]>>, <<$a->[1] / $a->[0]>>)

   rec()
   record()
      A valuation that just returns the entire record.

   snip(snip)
      Takes a snippet and returns both the snippet and the snippet as a
      valuation. Used to distinguished snippets from scalars in cases where it
      matters, e.g. min('{{x}}') interprets it is a keyspec when it was meant to
      be a snippet (and then a valuation), min(snip('{{x}}')) does what is
      intended. This is used internally by <<...>> and in fact <<...>> just
      translates to snip('...').

   subset_agg(<snippet>, <aggregator>)
   subset_aggregator(<snippet>, <aggregator>)
      Takes a snippate to act as a record predicate and an aggregator and
      produces an aggregator that acts as the provided aggregator as run on the
      filtered view.

      Example(s):
          An aggregator that counts the number of records with a time not above 6 seconds:
             subset_agg(<<{{time_ms}} <= 6000>>, ct())

   type_agg(obj)
   type_scalar(obj)
   type_val(obj)
      Force the object into a specific type. Can be used to force certain
      upconversions (or avoid them).

   valuation(sub { ... })
   val(sub { ... })
      Takes a subref, creates a valuation that represents it. The subref will
      get the record as its first and only argument.

      Example(s):
         To get the square of the "x" field:
            val(sub{ $[0]->{x} ** 2 })

   xform(<aggregator>, <snippet>)
      Takes an aggregator and a snippet and produces an aggregator the
      represents invoking the snippet on the aggregator's result.

      Example(s):
         To take the difference between the first and second time fields of the record collection:
            xform(recs(), <<{{1/time}} - {{0/time}}>>)

Help from: --help-keygroups:
KEY GROUPS
   SYNTAX: !regex!opt1!opt2... Key groups are a way of specifying multiple
   fields to a recs command with a single argument or function. They are
   generally regexes, and have several options to control what fields they
   match. By default you give a regex, and it will be matched against all first
   level keys of a record to come up with the record list. For instance, in a
   record like this:

   { 'zip': 1, 'zap': 2, 'foo': { 'bar': 3 } }

   Key group: !z! would get the keys 'zip' and 'zap'

   You can have a literal '!' in your regex, just escape it with a \.

   Normally, key groups will only match keys whose values are scalars. This can
   be changed with the 'returnrefs' or rr flag.

   With the above record !f! would match no fields, but !f!rr would match foo
   (which has a value of a hash ref)

   Options on KeyGroups:
      returnrefs, rr  - Return keys that have reference values (default:off)
      full, f         - Regex should match against full keys (recurse fully)
      depth=NUM,d=NUM - Only match keys at NUM depth (regex will match against
                        full keyspec)
      sort, s         - sort keyspecs lexically

Help from: --help-keyspecs:
  KEY SPECS
   A key spec is short way of specifying a field with prefixes or regular
   expressions, it may also be nested into hashes and arrays. Use a '/' to nest
   into a hash and a '#NUM' to index into an array (i.e. #2)

   An example is in order, take a record like this:

     {"biz":["a","b","c"],"foo":{"bar 1":1},"zap":"blah1"}
     {"biz":["a","b","c"],"foo":{"bar 1":2},"zap":"blah2"}
     {"biz":["a","b","c"],"foo":{"bar 1":3},"zap":"blah3"}

   In this case a key spec of 'foo/bar 1' would have the values 1,2, and 3 in
   the respective records.

   Similarly, 'biz/#0' would have the value of 'a' for all 3 records

   You can also prefix key specs with '@' to engage the fuzzy matching logic

   Fuzzy matching works like this in order, first key to match wins
     1. Exact match ( eq )
     2. Prefix match ( m/^/ )
     3. Match anywehre in the key (m//)

   So, in the above example '@b/#2', the 'b' portion would expand to 'biz' and 2
   would be the index into the array, so all records would have the value of 'c'

   Simiarly, @f/b would have values 1, 2, and 3

   You can escape / with a \. For example, if you have a record:
   {"foo/bar":2}

   You can address that key with foo\/bar

Help from: --help-more:
Usage: recs-collate <args> [<files>]
   Take records, grouped togther by --keys, and compute statistics (like
   average, count, sum, concat, etc) within those groups.

   For starting with collate, try doing single --key collates with some number
   of aggregators (list available in --list-agrregators)

Arguments:
   --dlaggregator|-A ...                         Specify a domain language
                                                 aggregate. See "Domain Language
                                                 Integration" below.
   --aggregator|-a <aggregators>                 Colon separated list of
                                                 aggregate field specifiers. See
                                                 "Aggregates" section below.
   --mr-agg <name> <map> <reduce> <squish>       Specify a map reduce
                                                 aggregator via 3 snippets,
                                                 similar to mr_agg() from the
                                                 domain language.
   --ii-agg <name> <initial> <combine> <squish>  Specify an inject into
                                                 aggregator via 3 snippets,
                                                 similar to ii_agg() from the
                                                 domain language.
   --incremental                                 Output a record every time an
                                                 input record is added to a
                                                 clump (instead of every time a
                                                 clump is flushed).
   --[no]-bucket                                 With --bucket outputs one
                                                 record per clump, with --no-
                                                 bucket outputs one record for
                                                 each record that went into
                                                 the clump.
   --key|-k <keys>                               Comma separated list of key
                                                 fields. May be a key spec or
                                                 key group
   --dlkey|-K ...                                Specify a domain language key.
                                                 See "Domain Language
                                                 Integration" section in --help-
                                                 more.
   --size|--sz|-n <number>                       Number of running clumps to
                                                 keep.
   --adjacent|-1                                 Only group together adjacent
                                                 records. Avoids spooling
                                                 records into memeory
   --cube                                        See "Cubing" section in --help-
                                                 more.
   --clumper ...                                 Use this clumper to group
                                                 records. May be specified
                                                 multiple times. See --help-
                                                 clumping.
   --dlclumper ...                               Use this domain language
                                                 clumper to group records. May
                                                 be specified multiple times.
                                                 See --help-clumping.
   --list-aggregators|--list                     Bail and output a list of
                                                 aggregators
   --show-aggregator <aggregator>                Bail and output this
                                                 aggregator's detailed usage.
   --list-clumpers                               Bail and output a list of
                                                 clumpers
   --show-clumper <clumper>                      Bail and output this clumper's
                                                 detailed usage.
   --filename-key|fk <keyspec>                   Add a key with the source
                                                 filename (if no filename is
                                                 applicable will put NONE)

  Help Options:
      --help-aggregators     List the aggregators
      --help-all             Output all help for this script
      --help                 This help screen
      --help-clumping        Help on clumping; mechanisms to group records
                             across a stream
      --help-domainlanguage  Help on the recs domain language, a [very
                             complicated] way of specifying valuations (which
                             act like keys) or aggregators
      --help-keygroups       Help on keygroups, a way of specifying
                             multiple keys
      --help-keys            Help on keygroups and keyspecs
      --help-keyspecs        Help on keyspecs, a way to index deeply and
                             with regexes
      --help-more            Larger help documentation

Examples:
   Count clumps of adjacent lines with matching x fields.
      recs-collate --adjacent --key x --aggregator count
   Count number of each x field value in the entire file.
      recs-collate --key x --aggregator count
   Finds the maximum latency for each date, hour pair
      recs-collate --key date,hour --aggregator worst_latency=max,latency
   Find the median value of x+y in records
      recs-collate --dlaggregator "m=perc(50,snip(<<{{x}}+{{y}}>>))"

Aggregates:
   Aggregates are specified as [<fieldname>=]<aggregator>[,<arguments>]. The
   default field name is aggregator and arguments joined by underscores. See --list-
   aggregators for a list of available aggregators.

   Fieldname maybe a key spec. (i.e. foo/bar=sum,field). Additionally, all key
   name arguments to aggregators maybe be key specs (i.e. foo=max,latency/url),
   but not key groups

Cubing:
   Instead of added one entry for each input record, we add 2 ** (number of key
   fields), with every possible combination of fields replaced with the default
   of "ALL". This is not meant to be used with --adjacent or --size. If our key
   fields were x and y then we'd get output records for {x = 1, y = 2}, {x = 1,
   y = ALL}, {x = ALL, y = 2} and {x = ALL, y = ALL}.

Domain Lanuage Integration:
   The normal mechanism for specifying keys and aggregators allows one to
   concisely instantiate the objects that back them in the platform and is
   certainly the easiest way to use recs. The record stream domain language
   allows the creation of these objects in a programmatic way, with neither the
   syntactic issues of the normal way nor its guiding hand.

   The domain language is itself just Perl with a collection of library
   functions for creating platform objects included. Your favorite aggregators
   are all here with constructors matching their normal token. For convenience
   of e.g. last, aggregators are also included with a prefixed underscore.

   Below you can find documentation on all the "built in" functions. Most
   aggregators and deaggregators should be present with arguments comparable to
   their normal instantiation arugments, but with keyspec parameters replaced
   with valuations parameters.

   Either aggregates or keys may be specified using the recs domain language.
   Both --dlkey and --dlaggregator require an options of the format
   '<name>=<domain language code>'. --dlkey requires the code evaluate as a
   valuation, --dlaggregator requires the code evaluate as an aggregator.

   See --help-domainlanguage for a more complete description of its workings and
   a list of available functions.

   See the examples below for a more gentle introduction.

Examples:
   Count clumps of adjacent lines with matching x fields.
      recs-collate --adjacent --key x --aggregator count
   Count number of each x field in the entire file.
      recs-collate --key x --aggregator count
   Count number of each x field in the entire file, including an "ALL" line.
      recs-collate --key x --aggregator count --cube
   Produce a cummulative sum of field profit up to each date
      recs-collate --key date --adjacent --incremental --aggregator profit_to_date=sum,profit
   Produce record count for each date, hour pair
      recs-collate --key date,hour --aggregator count
   Finds the maximum latency for each date, hour pair
      recs-collate --key date,hour --aggregator worst_latency=max,latency
   Produce a list of hosts in each datacenter.
      recs-collate --key dc --dlaggregator "hosts=uconcat(', ', 'host')"
   Sum all time fields
      recs-collate --key ... --dlaggregator 'times=for_field(qr/^t/, <<sum($f)>>)'
   Find the median value of x+y in records
      recs-collate --dlaggregator "m=perc(50,snip(<<{{x}}+{{y}}>>))"
   Count people by first three letters of their name
      recs-collate --dlkey "tla=<<substr({{name}},0,3)>>" -a ct

SEE ALSO