Accessing values of a field of a dataset

Hi,

I need to access the values of a field in a dataset but the trick is that I don't know in advance the column name: it's passed to me in a string variable. I'm including below some code to give an idea of what I have in mind.

Thanks in advance

>> TestDSAccess % call the function below from Matlab's prompt

%%%%these two functions go in file TestDSAccess.m
function TestDSAccess()
myDS=dataset([1;2],[3;4],'VarNames',{'F1','F2'})

% this works but I don't know the variable name in advance (see below)
myDS.F1

% I will receive the variable name as a string
addToValue(myDS, 'F1', 7)
end

function result = addToValue(dsVar, strFieldName, number)

% this work but is too verbose and I have to store the result back in dsVar(:, {strFieldName})
temp = double( dsVar(:, {strFieldName}) )
result = temp + number ; %%Works

% this returns another dataset, not what I am looking for
temp = dsVar(:, {strFieldName})
result = temp + number ; %%ERROR!!

% something like the following would be ideal:
dsVar(:, {strFieldName}).data + number; % illegal

end

Answer 1

[Daniel Shub]

You can use dynamic field names:

myDS=dataset([1;2],[3;4],'VarNames',{'F1','F2'});
strFieldName = 'F1';
myDS.(strFieldName)

[Mark]

Thank you, that worked.