Mac installation - could not load librefprop.dylib - incompatible architecture

[matlawicebox]

My cmake --build installation on Mac ran without errors, but I'm still at a loss how to get it to work with CoolProp. I moved a copy of the generated file librefprop.dylib to where I think it's supposed to go (/usr/local/bin), as well as FLUIDS folder and for good measure the REFPROP folder that was generated on my Windows machine after installation, but I get errors when I first try to use REFPROP within CoolProp (even after explicitly setting /usr/local/bin as the REFPROP path). It looks like there's something wrong with the generated librefprop.dylib file and/or path issue (I've checked and /usr/local/bin is in my path).

I'm not even sure if I have one problem (librefprop not compatible with my gcc/gfortran?) or two problems (also not finding REFPROP folder?) If it's the first, I followed the instructions using gcc/gfortran from Macports - I can't see how to change the architecture for those.

Any suggestions what to try next greatly appreciated!!

import CoolProp.CoolProp as CP
CP.set_config_string(CP.ALTERNATIVE_REFPROP_PATH, '/usr/local/bin')
testAS=CP.AbstractState('REFPROP','R1234yf&R134a'); REFPROP.set_mole_fractions([0.56,0.44])

yielding

Good news: It is possible to use REFPROP on your system! However, the library 
could not be loaded. Please make sure that REFPROP is available on your system.
Neither found in current location nor found in system PATH.
If you already obtained a copy of REFPROP from http://www.nist.gov/srd/, 
add location of REFPROP to the PATH environment variable or your library path.
In case you do not use Windows, have a look at https://github.com/jowr/librefprop.so 
to find instructions on how to compile your own version of the REFPROP library.
ALTERNATIVE_REFPROP_PATH: /usr/local/bin
ERROR: Could not load REFPROP (librefprop.dylib) due to: dlopen(/usr/local/bin/librefprop.dylib, 0x0002): tried: '/usr/local/bin/librefprop.dylib' (mach-o file, but is an incompatible architecture (have 'arm64', need 'x86_64')), '/System/Volumes/Preboot/Cryptexes/OS/usr/local/bin/librefprop.dylib' (no such file), '/usr/local/bin/librefprop.dylib' (mach-o file, but is an incompatible architecture (have 'arm64', need 'x86_64')). Make sure the library is in your system search path. In case you run 64bit Windows and you have a REFPROP license, try installing the 64bit DLL from NIST. 
Traceback (most recent call last):
  File "/Users/matlawicebox/Desktop/Python/HeatPump/venv/lib/python3.8/site-packages/IPython/core/interactiveshell.py", line 3378, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-4-ee9a4c0c2915>", line 1, in <module>
    testAS=CP.AbstractState('REFPROP','R1234yf&R134a'); REFPROP.set_mole_fractions([0.56,0.44])
  File "CoolProp/AbstractState.pyx", line 32, in CoolProp.CoolProp.AbstractState.__cinit__
ValueError: You cannot use the REFPROPMixtureBackend.

[ianhbell]

Welcome to the joys of dealing with arch on mac. You built an arm64 binary but your python is x86_64. You need to resolve, that, and I always use conda, and that seems to be a very reliable solution. In conda it will show you what arch your python is and also for other binary packages.

[matlawicebox]

Can I try your homebrew method to get a c86_64 binary: Use the gfortran from homebrew and build for x86_64 and use Rosetta2 emulation?

I started trying this but I have no idea what the gfortran directory is on my Mac after homebrew gcc install. Doesn't show up in any finder searches (gcc or gfortran) - any ideas how I find that? Doesn't seem indicated in any of the output during the home-brew install.

I have a whole python venv up and running with a bunch of code that I don't want to have to redo (so don't want to move to anaconda). I'm just trying to get access to some fluid mixtures that CoolProp sometimes works with and sometimes doesn't...

[ianhbell]

Personally I just bit the bullet and jumped two-feet into arm64. It is much less painful than mixed-arch with emulation

[ianhbell]

The other heavier solution is to run the other stuff in a docker container, if you already use docker

[matlawicebox]

Ok, I bit the bullet and did a miniconda3 install of python. I also moved a copy of librefprop.dylib to /opt/refprop (where it seemed to be looking for it) along with FLUIDS folder. Still have an error (but different this time) when I run these 3 lines of code:

import CoolProp.CoolProp as CP
testAS=CP.AbstractState('REFPROP','R1234yf&R134a'); REFPROP.set_mole_fractions([0.56,0.44])
print(testAS)

yielding

Traceback (most recent call last):
  File "/Users/matlawicebox/Desktop/Python/CondaHeatPump/testrefprop.py", line 3, in <module>
    testAS=CP.AbstractState('REFPROP','R1234yf&R134a'); REFPROP.set_mole_fractions([0.56,0.44])
NameError: name 'REFPROP' is not defined

[matlawicebox]

Oh, I that was me cutting and pasting wrong (not replacing a "REFPROP" with variable name). This now works:

import CoolProp
R513a = CoolProp.AbstractState('REFPROP','R1234yf&R134a'); R513a.set_mole_fractions([0.56,0.44])

[ianhbell]

Good!

P.S. You can a) edit your post (the three dots) or b) add three backticks (a backtick is a `) to surround code blocks so they render as code