Summing Channel History

[KenMandile]

I am monitoring the status of our CNC machine tools.  A zero means the machine is running and a 1 means that it is not running.  I want to calculate the average run time for the past hour, so I need to sum my readings.  I know that if my total of the 1200 data points is zero (reads once every 3 seconds) then the machine ran 100% of the time.

Is there a function for summing the values in the channel history?

[AzeoTech]

Sure:

 

sum(myChannel)

 

though in your case its the "anti-sum" so to speak.  You want:

 

sum(myChannel == 0)

 

Or if you want just the last hour:

 

sum(myChannel[systime(), systime()-3600] == 0)