snap_stats

Purpose:

Perform statistical computations such as mean, standard deviation, minimum, and maximum for specified variables, synchronized by external events.

Enter:

snap_stats <reg_name> <priority> <interval> [+c] &

Where:

reg_name

Specify a unique registration name for multiple instances.

priority

Specify the system priority level.

interval

Specify the time interval in milliseconds for scheduler signaling.

+c

Optional. Specify this flag to indicate the process is considered to be a critical task. The watchdog will be triggered if the process abnormally terminates.

Example:

snap_stats SnapStat121000 &

The above spawns the Snap Statistics process, snap_stats at a system priority level of 12 and would signal the master scheduler once every second. The registered name of this instance will be “SnapStat”.

Configure the “snap_stats” application using the “snap_specs” translator application. The default spec file name is /specs/ss_specs.NNN (where NNN is the test cell name). 

Below is an example spec file:

# the @REG_NAME keyword is optional – the default registered name is SnapStat  
@REG_NAME  
   SnapStat  
 
####################################################################  
# this is an example specification file for the snap_stats task  
#  
# There can be 8 groups of specs in this file, each with a distinct  
# set of controlling events.  Each group can have 64 variables.  
#  
# Separate each group with a $ symbol  
#  
#######################################################################  
#sample_event   compute_event     compute_done_event   clear_event  
take_sample     compute_result    compute_done         clear_buffers  
 
#list of variables ( 100 max )  
#in_variable      stat_variable(output)  
my_x              my_x.  
my_x2             my_x2.  
my_x3             my_stat.  
#ldots  
#  
$  
 
#sample_event   compute_event     compute_done_event   clear_event  
sample          compute_result    –                    clear_buffers  
 
#list of variables ( 100 max )  
#variable      stat_variable(output)  
an_x           an_x.  
#ldots  
 
$

Notes:

Ensure the program is configured via appropriate tools for optimal operation.

See Also:

snap_specs, Statistical Variables and Sampling