MATLAB: Calculation with strcmp with variable values

Question

Hello,

I have the following three tables:

Tab1=table('Size',[9 3],'VariableTypes',{'cell','double','double'},'VariableNames',{'Description','Year','Value'});
Tab1.Description(:)={'Gas','Gas','Gas','Pellets','Pellets','Pellets','Oil','Oil','Oil'};
Tab1.Year(:)=[2015,2020,2025,2015,2020,2025,2015,2020,2025];
Tab1.Value(:)=[5,10,17,7,25,75,23,47,54];
Tab2=table('Size',[6 3],'VariableTypes',{'cell','double','double'},'VariableNames',{'Description','Year','Value'});
Tab2.Description(:)={'Gas','Gas','Gas','Oil','Oil','Oil'};
Tab2.Year(:)=[2015,2020,2025,2015,2020,2025];
Tab3=table('Size',[3 2],'VariableTypes',{'double','double'},'VariableNames',{'Year','Value'});
Tab3.Year(:)=[2015,2020,2025];
Tab3.Value(:)=[1002,3007,2001];

I am searching for a way, to simplify the following calculation:

for i=1:3
    Tab2{strcmp(Tab2.Description,'Gas'),'Value'}(i)=Tab1{strcmp(Tab1.Description,'Gas'),'Value'}(i)*Tab3{i,'Value'};
    Tab2{strcmp(Tab2.Description,'Oil'),'Value'}(i)=Tab1{strcmp(Tab1.Description,'Oil'),'Value'}(i)*Tab3{i,'Value'};
end
clear i;

Imagine Tab1 and Tab2 are way bigger and there are way more different Values in the "Description"-column, then the solution above would be inappropriate.

I thought about something like:

for i=1:3
    Tab2{strcmp(Tab2.Description,'X'),'Value'}(i)=Tab1{strcmp(Tab1.Description,'X'),'Value'}(i)*Tab3{i,'Value'};
end
clear i;

where X can have all the different Descriptions from Tab2. But i don´t know how to do it in MATLAB.

I will greatly appreciate any assistance.

Answer 1

[C,idx1,idx2] = innerjoin(Tab1,Tab2, "LeftKeys",{'Description','Year'},"RightKeys",{'Description','Year'});
[~,idx3] = join(C, Tab3, "Keys","Year");
Tab2.Value(idx2) = Tab1.Value(idx1).*Tab3.Value(idx3);