Matlab spmd and CoolProp (CPython library)

Hi everone,

when i want to run the following code block in matlab spmd in Windows 11,

CP = py.importlib.import_module('CoolProp');

Fluid = CP.AbstractState("HEOS", 'water');

n = 4;

T = 300 + 273.15;

P = 100;

spmd (n)

T = T + 10*spmdIndex;

Fluid.update(CP.PT_INPUTS, P*1000, T);

Fluid.cpmass();

Fluid.rhomass();

Fluid.conductivity();

Fluid.viscosity();

end

I got the error shown in below;

Worker 1:

Warning: Unable to load Python object. Saving (serializing) Python objects into a MAT-file is not supported.

> In parallel.internal.pool.deserialize (line 33)

In parallel.internal.pool.deserializeFunction (line 17)

In spmdlang.remoteBlockExecution>iDeserializeInputs (line 59)

In spmdlang.remoteBlockExecution>iUnpackPreludeArgs (line 46)

In spmdlang.remoteBlockExecution (line 12)

Warning: Unable to load Python object. Saving (serializing) Python objects into a MAT-file is not supported.

> In parallel.internal.pool.deserialize (line 33)

In parallel.internal.pool.deserializeFunction (line 17)

In spmdlang.remoteBlockExecution>iDeserializeInputs (line 59)

In spmdlang.remoteBlockExecution>iUnpackPreludeArgs (line 46)

In spmdlang.remoteBlockExecution (line 12)

What can I do for this problem, I will be glad if you help me....

Answer 1

[Edric Ellis]

You need to avoid transferring the objects to the workers, and instead simply build the objects directly on the workers. The simplest way to do this is to move the lines creating CP and Fluid inside your spmd block, like this:

n = 4;
T = 300 + 273.15;
P = 100;
spmd (n)
    CP = py.importlib.import_module('CoolProp');  
    Fluid = CP.AbstractState("HEOS", 'water');
    
    T = T + 10*spmdIndex;
    ...
end

[Ibrahim KAYA]

it's working, thanks a lot.