Scripting

[mariosp]

Hello guys i made a script and i need you help 
I have underfloor heating and i want to make zones o pwm vavles . what i mean that if the setpoint bigger than the actual temperature by 1C then the valves must be open 100% , if the setpoint bigger than the actual temperature by 0.7 C then the valves must be open 75% and so on.
here is the scrpict that i made but doest work and i dont get any error 

-- zone* = value of the valve
zone0 = 0
  zone1 = 25
  zone2 = 50
  zone3 = 75
  zone4 = 100
-- 3/1/1 set point
-- 12/0/5 actual temperature
  if grp.getvalue('3/1/1') > grp.getvalue('12/0/5') - 1
    then grp.write('4/1/1',zone4)
      elseif
          grp.getvalue('3/1/1') > grp.getvalue('12/0/5') - 0.7
            then grp.write('4/1/1',zone3)
              elseif
                  grp.getvalue('3/1/1') > grp.getvalue('12/0/5') - 0.5
                  then grp.write('4/1/1',zone2)
                    elseif
                  grp.getvalue('3/1/1') > grp.getvalue('12/0/5') - 0.3
                then grp.write('4/1/1',zone1)             
            elseif
          (grp.getvalue'3/1/1') == grp.getvalue('12/0/5')
      then grp.write('4/1/1',zone0)
 
   
end
thank you in advance