Arguments to IMPORT must either end with ".*" or else specify a fully qualified class name

Error: File: dens_times_SpeedOfSound_critical.m Line: 2 Column: 8

Arguments to IMPORT must either end with ".*" or else specify a fully qualified class name: "py.CoolProp.CoolProp.PropsSI" fails this test.

Why do I get the above error when I run the below script? (matlab2017b)

import py.CoolProp.CoolProp.PropsSI; 
P0 = 10:10:300;
T0 = 110:10:400;
c1 = [];
dens1 = [];
gamma = 1.304; 
T1 = 2*T0/(gamma+1);
P1 = P0/((gamma+1)/2)^(gamma/(gamma-1));
for i = 1:1:length(P1)
    for j = 1:1:length(T1)
        c1 = [c1,PropsSI('A','T',T1(j),'P',P1(i)*100000,'methane')];
        dens1 = [dens1,PropsSI('D','T',T1(j),'P',P1(i)*100000,'methane')];
    end
end
c1 = reshape(c1, [30,30]);
c1 = c1';
dens1 = reshape(dens1, [30,30]);
dens1 = dens1';
R1 = c1.*dens1;
[C,h] = contour(T0,P0,R1, [10000:10000:700000]);
clabel(C,h)commen
xlabel('T stagnation @ injector / k')
ylabel('P stagnation @ injector / bar')
title('Evolution of c1*dens1 as a function of T and P stagnation [kg/m2/s]')
mass_flow = (103.2/2000)/0.03;
Area1 = mass_flow./R1; %m2
diameter1 = 1000*sqrt(Area1.*4/pi()); %mm
figure
[D,t] = contour(T0,P0,diameter1, [0.5:0.5:15]);
clabel(D,t)
title('Injector diameter as a function of T and P stagnation [mm]')
xlabel('T stagnation @ injector / k')
ylabel('P stagnation @ injector / bar')

Answer 1

[TARUN]

Hi @Alejandro calvo

The issue is the compatibility of MATLAB with python’s version and the CoolProp version.

There are some versions of python that are not supported by MATLAB which is why the issue is arising.

You can check out the following MATLAB answer to know which versions are compatible and the workaround for this issue:

https://www.mathworks.com/matlabcentral/answers/525531-py-coolprop-coolprop-propssi-not-working