Arrays in PLC programming

HI sir;
I want to do the following task
i read the air inlet temprature from field and i want to get average of it after every two second and between 0 to 2 second the values store in a array when timer done bit is on it calculates the average.
Second opinion is that when 10 values are read out in an array it calculates the average.
I need help on this how i fullfill this task or any other opinion do u have?
Regards

What type of PLC?

Try this:

Hi sir
GE FUNAC PLC 90-30 series CPU 351.
Regards

Here's a quick idea maybe you could try something like this.
The Reading will not be correct for first 6 seconds. But you could add code to accomplish that too.