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Access data from table and assign to variables

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Dhananjay Singh
Dhananjay Singh on 27 Aug 2021
Answered: Campion Loong on 30 Aug 2021
Hi, I am making a program with excel file already converted to table and now I need to code such that when a user gives an input a certain coloumn is taken and then assign certain variables to some particular blocks in that row.
example:
Vehicle speed fuel
Car 50 2
Bike 20 1
Cycle 5 0
Like user gives input as Bike. then I need to assign variables created like speed and fuel to use in further equations.
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Accepted Answer

Ive J
Ive J on 27 Aug 2021
Edited: Ive J on 27 Aug 2021
This might work
tab = table({'Car'; 'Bike'; 'Cycle'}, [50; 20; 5], [2; 1; 0],...
'VariableNames', {'Vehicle', 'speed', 'fuel'})
tab = 3×3 table
Vehicle speed fuel _________ _____ ____ {'Car' } 50 2 {'Bike' } 20 1 {'Cycle'} 5 0
filterIn = 'Bike'; %input('what to filter? ', 's');
idx = ismember(tab.Vehicle, filterIn);
if ~any(idx)
fprintf('oops, not found!\n')
return
end
dataTable = tab(idx, :);
dataStruct = table2struct(dataTable, 'ToScalar', true);
as table:
disp(dataTable)
Vehicle speed fuel ________ _____ ____ {'Bike'} 20 1
or struct:
disp(dataStruct)
Vehicle: {'Bike'} speed: 20 fuel: 1
  2 Comments
Ive J
Ive J on 27 Aug 2021
Yes you can easily assign struct fields to variables, but it's better to use structs as they are, it's much easier and more clear!
x = dataStruct.speed; % or other field names, see fieldnames help

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More Answers (1)

Campion Loong
Campion Loong on 30 Aug 2021
Picking up from @Ive J's example, but use 'Vehicle' as Row Labels to take advantage of native table indexing:
t = table([50; 20; 5], [2; 1; 0], 'VariableNames', ["speed", "fuel"], 'RowNames', ["Car"; "Bike"; "Cycle"])
t = 3×2 table
speed fuel _____ ____ Car 50 2 Bike 20 1 Cycle 5 0
t("Bike", ["speed", "fuel"]) % or if you want all variables, t("Bike", :)
ans = 1×2 table
speed fuel _____ ____ Bike 20 1

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