Relay Ladder; Structured Text - Allen-Bradley Logix5000 Reference Manual

Chapter 8 Array (File)/Misc. Instructions (FAL, FSC, COP, CPS, FLL, AVE, SRT, STD, SIZE)
16 + 11 + + 6
------------------------------------ -
AVE =
4
 
16 8.5 –
STD = -------------------------------------------------------------------------------------------------------------------------- -
real_std = 6.454972
394
Example 1:
Calculate the standard deviation of dint_array, which is DINT[4,5].
1 34
----- -
= = 8.5
4
2 2
  
+ 11 8.5 – + 6 8.5 –
 
4 1 –

Relay Ladder

Structured Text

SIZE(dint_array,0,length);
sum := 0;
FOR position = 0 TO (length-1) DO
sum := sum + dint_array[position];
END_FOR;
average := sum / length;
sum := 0;
FOR position = 0 TO (length-1) DO
sum := sum + ((dint_array[position] - average)**2);
END_FOR;
real_std := SQRT(sum / (length-1));
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Dimension 0
2 2
  
+ 1 8.5 –
= 6.454972
Dimension 1
0 1 2 3
20 19 18 17
0
15 14 13 12
1
10 9 8 7
2
5 4 3 2
3
4
16
11
6
1