Logical expressions are formed similar to FORTRAN. They may contain numerical comparisons using the syntax: <arithmetic expression> <operator> <arithmetic expression>. The allowed operators within KUPLOT are .lt., .le., .gt., .ge., .eq. and .ne. for operations less than, less equal, greater than, greater equal, equal and not equal, respectively.
Logical expressions can be combined by the logical operators .not., .and. and or. The following example shows an expression that is true for values of i[1] within the interval of 3 and 11, false otherwise.
i[1].ge.3 .and. i[1].le.11
Logical operations may be nested and grouped using round brackets ( and ). For more examples see section 6.6.