function isWhole returns logical (p-dec as decimal):
return (p-dec >=0 and p-dec = truncate( p-dec, 0 ) ).
end function.
display
isWhole( 3.5 ) /* no */
isWhole( 4 ) /* yes */
isWhole( -1 ) /* no */
isWhole( 0 ) /* yes */
.
┌───────────────┐
│no yes no yes│
└───────────────┘