Eph1 = 2.165# actual photon energy
Eph2 = 2.185  # desired photon energy

# beam on-delay during change!

undlist = ("SARUN03","SARUN04","SARUN05","SARUN06","SARUN07","SARUN08","SARUN09","SARUN10","SARUN11","SARUN12","SARUN13","SARUN14","SARUN15")


for und in undlist:
  K1 = caget(und + "-UIND030:K_SET")
  K2 = ((Eph1 / Eph2 * (K1**2 + 2) - 2))**0.5
  print K1,K2
  caput(und + "-UIND030:K_SET",  0.07)
  time.sleep(10.0)
  caput(und + "-UIND030:K_SET",  K2)
print "finished"