How do I Identify/Sum the THREE highest values

[Reeza]

Are you summing based on rows or columns? It's not clear. Please post what your output would be for sample data and the code you have so far. 

[Reeza · Accepted solution]

You need some basic array processing. 

1. Declare an array

array ais(*) abd_ais ext_ais .... ; *list of ais vars;

2. Set to 75 if necessary. 

If max(of ais(*))>5 then iss=75;

3. Else sure the 3 largest values - Use LARGEST() function. 

else iss = largest(1, of ais(*))**2 + largest(2, of ais(*))**2 + largest(3, of ais(*))**2;