counter(n)                  Counters and Histograms                 counter(n)



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NAME
       counter - Procedures for counters and histograms

SYNOPSIS
       package require Tcl  8

       package require counter  ?2.0.4?

       ::counter::init tag args

       ::counter::count tag ?delta? ?instance?

       ::counter::start tag instance

       ::counter::stop tag instance

       ::counter::get tag args

       ::counter::exists tag

       ::counter::names

       ::counter::histHtmlDisplay tag args

       ::counter::reset tag args

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DESCRIPTION
       The counter package provides a counter facility and can compute
       statistics and histograms over the collected data.

       ::counter::init tag args
              This defines a counter with the name tag.  The args determines
              the characteristics of the counter.  The args are

              -group name
                     Keep a grouped counter where the name of the histogram
                     bucket is passed into ::counter::count.

              -hist bucketsize
                     Accumulate the counter into histogram buckets of size
                     bucketsize.  For example, if the samples are millisecond
                     time values and bucketsize is 10, then each histogram
                     bucket represents time values of 0 to 10 msec, 10 to 20
                     msec, 20 to 30 msec, and so on.

              -hist2x bucketsize
                     Accumulate the statistic into histogram buckets.  The
                     size of the first bucket is bucketsize, each other bucket
                     holds values 2 times the size of the previous bucket.
                     For example, if bucketsize is 10, then each histogram
                     bucket represents time values of 0 to 10 msec, 10 to 20
                     msec, 20 to 40 msec, 40 to 80 msec, and so on.

              -hist10x bucketsize
                     Accumulate the statistic into histogram buckets.  The
                     size of the first bucket is bucketsize, each other bucket
                     holds values 10 times the size of the previous bucket.
                     For example, if bucketsize is 10, then each histogram
                     bucket represents time values of 0 to 10 msec, 10 to 100
                     msec, 100 to 1000 msec, and so on.

              -lastn N
                     Save the last N values of the counter to maintain a
                     "running average" over the last N values.

              -timehist secsPerMinute
                     Keep a time-based histogram.  The counter is summed into
                     a histogram bucket based on the current time.  There are
                     60 per-minute buckets that have a size determined by
                     secsPerMinute, which is normally 60, but for testing
                     purposes can be less.  Every "hour" (i.e., 60 "minutes")
                     the contents of the per-minute buckets are summed into
                     the next hourly bucket.  Every 24 "hours" the contents of
                     the per-hour buckets are summed into the next daily
                     bucket.  The counter package keeps all time-based
                     histograms in sync, so the first secsPerMinute value seen
                     by the package is used for all subsequent time-based
                     histograms.

       ::counter::count tag ?delta? ?instance?
              Increment the counter identified by tag.  The default increment
              is 1, although you can increment by any value, integer or real,
              by specifying delta.  You must declare each counter with
              ::counter::init to define the characteristics of counter before
              you start to use it.  If the counter type is -group, then the
              counter identified by instance is incremented.

       ::counter::start tag instance
              Record the starting time of an interval.  The tag is the name of
              the counter defined as a -hist value-based histogram.  The
              instance is used to distinguish this interval from any other
              intervals that might be overlapping this one.

       ::counter::stop tag instance
              Record the ending time of an interval.  The delta time since the
              corresponding ::counter::start call for instance is recorded in
              the histogram identified by tag.

       ::counter::get tag args
              Return statistics about a counter identified by tag.  The args
              determine what value to return:

              -total Return the total value of the counter.  This is the
                     default if args is not specified.

              -totalVar
                     Return the name of the total variable.  Useful for
                     specifying with -textvariable in a Tk widget.

              -N     Return the number of samples accumulated into the
                     counter.

              -avg   Return the average of samples accumulated into the
                     counter.

              -avgn  Return the average over the last N samples taken.  The N
                     value is set in the ::counter::init call.

              -hist bucket
                     If bucket is specified, then the value in that bucket of
                     the histogram is returned.  Otherwise the complete
                     histogram is returned in array get format sorted by
                     bucket.

              -histVar
                     Return the name of the histogram array variable.

              -histHour
                     Return the complete hourly histogram in array get format
                     sorted by bucket.

              -histHourVar
                     Return the name of the hourly histogram array variable.

              -histDay
                     Return the complete daily histogram in array get format
                     sorted by bucket.

              -histDayVar
                     Return the name of the daily histogram array variable.

              -resetDate
                     Return the clock seconds value recorded when the counter
                     was last reset.

              -all   Return an array get of the array used to store the
                     counter.  This includes the total, the number of samples
                     (N), and any type-specific information.  This does not
                     include the histogram array.

       ::counter::exists tag
              Returns 1 if the counter is defined.

       ::counter::names
              Returns a list of all counters defined.

       ::counter::histHtmlDisplay tag args
              Generate HTML to display a histogram for a counter.  The args
              control the format of the display.  They are:

              -title string
                     Label to display above bar chart

              -unit unit
                     Specify minutes, hours, or days for the time-base
                     histograms.  For value-based histograms, the unit is used
                     in the title.

              -images url
                     URL of /images directory.

              -gif filename
                     Image for normal histogram bars.  The filename is
                     relative to the -images directory.

              -ongif filename
                     Image for the active histogram bar.  The filename is
                     relative to the -images directory.

              -max N Maximum number of value-based buckets to display.

              -height N
                     Pixel height of the highest bar.

              -width N
                     Pixel width of each bar.

              -skip N
                     Buckets to skip when labeling value-based histograms.

              -format string
                     Format used to display labels of buckets.

              -text boolean
                     If 1, a text version of the histogram is dumped,
                     otherwise a graphical one is generated.

       ::counter::reset tag args
              Resets the counter with the name tag to an initial state. The
              args determine the new characteristics of the counter. They have
              the same meaning as described for ::counter::init.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain
       bugs and other problems.  Please report such in the category counter of
       the Tcllib SF Trackers
       [http://sourceforge.net/tracker/?group_id=12883].  Please also report
       any ideas for enhancements you may have for either package and/or
       documentation.

KEYWORDS
       counting, histogram, statistics, tallying

CATEGORY
       Data structures



counter                              2.0.4                          counter(n)
