invalid use of matlabfunction 'tablelookup' in simscape component

I keep getting an error when I try to run a simle electrical circuit with my custom resistor connected.

The error occursin the line (in the equations section) where I define R as a function of Temperature [T] and State of Charge (of the battery cell) [SoC].

R == tablelookup(Td, SoCd, R_tab, T, SoC, interpolation = smooth);

I have defined SoCd as a 1 x 11 vector ranging from 0 to 1 .

I have defined Td as 1 x 3 vector ranging from 273.15 'K' to 313.15 'K' .

I have defined the table with values for R as R_tab, which is a 11 x 3.

What is going wrong in my code?

component MyElecResistor
    % Electrical resistor
    % This electrical resistor featues a constant electrical resistance 
    % This electrical resistance generates a heatflow as P=I*V=I*I*R
    
    
    %Declarations
    variables
        i = {1,'A'};      % electrical current
        v = {1,'V'};      % voltage
    end
    
    parameters
        Td = {[273.15, 293.15, 313.15], 'K'}            % breakpoints temperature
        SoCd ={[0: 0.1: 1],'1'}                         % breakpoints state of charge
        R_tab = {   [0.012,  0.009,  0.0085;
                     0.012,  0.009,  0.0085;
                     0.0118, 0.0091, 0.0086;
                     0.0112, 0.009,  0.0085;
                     0.017,  0.0089, 0.0084;
                     0.011,  0.0088, 0.0082;
                     0.0109, 0.009,  0.0083;
                     0.0109, 0.0091, 0.0084;
                     0.0108, 0.0092, 0.0084;
                     0.0116, 0.009,  0.0085;
                     0.012,  0.0089, 0.0085], 'Ohm'};   % table values of R        
    end
    
    inputs
       T = {298.15, 'K'};   % T:left
       SoC = {1, '1'};      % SoC:left
    end
    
    outputs
        pow = {0.3, 'W'};                           % pow:right
    end
    
    nodes
        pos = foundation.electrical.electrical;     % +:left
        neg = foundation.electrical.electrical;     % -:right
    end
    
    %Relationships
    branches
        i: pos.i -> neg.i;
    end
    
    equations
        R == tablelookup(Td, SoCd, R_tab, T, SoC, interpolation = smooth);
        assert(T<={313.15, 'K'})
        assert(T>={273.15, 'K'})
        assert(SoC>=0)
        assert(SoC<=1)
            v == pos.v - neg.v;
            v == i*R;
            pow == i*v;
    end
end    

Answer 1

[Danvir Sethi]

You need to define 'R' as a variable

variables
        i = {1,'A'};      % electrical current
        v = {1,'V'};      % voltage
        R = {1, 'Ohm'};
 end