CMake config from 3.1.9 returns not found

[nyue]

CMake Error at CMakeLists.txt:17 (find_package):
  Found package configuration file:

    /home/nyue/systems/Imath/3.1.9/lib/cmake/Imath/ImathConfig.cmake

  but it set Imath_FOUND to FALSE so package "Imath" is considered to be NOT
  FOUND.

[meshula]

I can't guess what the problem is from that information, but the first thing I would do is to inspect the files in lib/cmake/Imath versus what you expect, and versus what is actually on your disk; maybe report your findings here and we might be able to help?