NAME
cfetoolcheck - Check a new value against the averages currently in the
database
SYNOPSIS
cfetool check name --value│-V value [--path│-p directory name]
[--time│-t seconds] [--daily│-d] [--weekly│-w] [--yearly│-y]
[--histograms│-H] [--verbose│-v] [--help│-h]
DESCRIPTION
Takes a new value and checks it against the averages currently in the
database specified by name, located at the path specified by the -p
argument, or the current working directory if the -p argument is
ommitted. The value will be associated with the current time, unless
the -t option is given. The output indicates how much higher or lower
the new value is compared to the averages in the database, in terms of
the number of standard deviations.
The -d, -w and -y options specify the databases to check the new value
against. If all three options are omitted, only the weekly database
will be accessed.
OPTIONS
--value│-v value
Specifies the new value to check against the database averages.
--path│-p directory name
The directory in which the database specified by name can be found.
--time│-t
The time the value was collected, in seconds since epoch (January
1st, 1970). If this argument is omitted, the current time will be
used.
--daily│-d
Check the new value against the daily averages database.
--weekly│-w
Check the new value against the weekly averages database.
--yearly│-y
Check the new value against the yearly averages database.
--histograms│-H
Check which histogram bucket the new value would fall into. The
histogram is divided into 64 buckets, which represent distances
from the mean value. Bucket 64 represents two standard deviations
above the expected value, and bucket 0 represents two standard
deviations below the expected value.
--verbose│-v
Print details of the command’s execution to the standard output
stream.
--help│-h
Print a short help message and then exit.
OUTPUT
Before exiting, "cfetool check" will print one line to the standard
output stream, in the following format:
yrly=ynum,bkt=ybkt;wkly=wnum,bkt=wbkt;dly=dnum,bkt=dbkt
ybkt, wbkt and dbkt represent the histogram bucket the given value
falls into, and will be 0 for databases that are not being checked
against, and if there is no histogram file or the -H option was not
specified.
ynum, wnum and dnum will be either the number 0 if the corresponding
database was not updated, or a code indicating the state of the given
statistic, as compared to an average of equivalent earlier times, as
specified below:
code high│low│normal meaning
-------------------------------------------------------------
-2 - no sigma variation
-------------------------------------------------------------
-4 low within noise threshold, and within
-5 normal 2 standard deviations from
-6 high expected value
-------------------------------------------------------------
-14 low microanomaly: within noise
-15 normal threshold, but 2 or more standard
-16 high deviations from expected value
-------------------------------------------------------------
-24 low normal; within 1 standard deviation
-25 normal from the expected value
-26 high
-------------------------------------------------------------
-34 low dev1; more than 1 standard
-35 normal deviation from the expected
-36 high value
------------------------------------------------------------
-44 low dev2; more than 2 standard
-45 normal deviations from the expected
-46 high value
-------------------------------------------------------------
-54 low anomaly; more than 3 standard
-55 normal deviations from the expected
-56 high value
Where "low" indicates that the current value is below both the expected
value for the current time position, and the global average value.
"high" indicates that the current value is above those values. "normal"
indicates that the current value is within the range of expected
values.
"cfetool check" also exits with a code corresponding to the above
table. If more than one database is being checked against, the most
negative result from all checks is returned, and the individual results
must be obtained from the standard output stream, as described above.
EXAMPLE
% cfetool check temperature --path /my/path --value 20 --histograms
yrly=0,bkt=0;wkly=-6,bkt=51;dly=0,bkt=0
Checks the value 20 against the weekly temperature database and
histogram files located in /my/path/ using the current time. The output
indicates that the new value given was within cfetool’s noise
threshold, and also within 2 standard deviations of the previous
average stored in the weekly database.
AUTHORS
The code and documentation were contributed by Stanford Linear
Accelerator Center, a department of Stanford University. This
documentation was written by
Elizabeth Cassell <e_a_c@mailsnare.net> and
Alf Wachsmann <alfw@slac.stanford.edu>
COPYRIGHT AND DISCLAIMER
Copyright 2004 Alf Wachsmann <alfw@slac.stanford.edu> and
Elizabeth Cassell <e_a_c@mailsnare.net>
All rights reserved.