IAND returns the logical AND of its arguments
.-,-. V | >>-IAND(-x,---y-+-)--------------------------------------------><
If any argument is not REAL FIXED BIN(p,0), then it is converted to SIGNED REAL FIXED BIN(p,0).
If any argument is SIGNED, then any UNSIGNED arguments are converted to SIGNED.
The result is REAL FIXED BIN( max(p1,p2,...), 0 ). It is UNSIGNED if all the arguments are UNSIGNED.