Relational operators are used with if, while statements. Relational operators like in Verilog, return true or fales of relation being checked.

• The result is a scalar value (example a < b)
• 0 if the relation is false (a is bigger then b)
• 1 if the relation is true ( a is smaller then b)
• x if any of the operands has unknown x bits or z bits (if a or b contains X or Z)

Note: If any operand is x or z, then the result of that test is treated as false (0)

 1 program relational {
 2   integer a = 5;
 3   bit [7:0] b = 10; 
 4   bit [3:0] c = 4'b10zx;
 5   printf (" %4d  <=  %8d = %b\n", a,b,(a  <= b));
 6   printf (" %4d  >=  %8d = %b\n", a,b,(a  >= b));
 7   printf (" %b  <=  %b = %b\n", c,b,(c  <= b));
 8   printf (" %b  <=  %b = %b\n", c,b,(c  <= b));  
 9 }

     5  <=        10 = 1
     5  >=        10 = 0
  10zx  <=  00001010 = x
  10zx  <=  00001010 = x

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