How to add multiple variables to a structure

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Afzal on 13 Jan 2023
Commented: Stephen23 on 14 Jan 2023
I have a cell ('varNames') containing variable names that I want to add to a structure ('s'). I am currently acheiving this using the evaluate command as:
for i=1:length('varNames')
However, I want to avoid using the evaluate command, as I will be using this code inside a parfor loop to speed up Simulink simulations. I have so far tried the solution here with a method to extract variable names described here as:
getname = @(x) inputname(1);
makeStruct = @(x) struct(getname(x),x);
s = cellfun(makeStruct, varNames);
But it just adds the variable names to the structure 's', not the actual variables. The variables are structures themseleves generated by the ToWorkspace blocks of Simulink.
  1 Comment
Stephen23 on 13 Jan 2023
Edited: Stephen23 on 13 Jan 2023
EVAL is completely unnecessary, the approaches you link to are... very complex.
As Jiri Hajek shows, all you need is INPUTNAME() and this:

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Answers (1)

Jiri Hajek
Jiri Hajek on 13 Jan 2023
Hi, eval is indeed completely unnecessary for your assignment.To create a new field in a structure, for which you have a name defined by a character vector or a string, use parentheses.
s.(newFieldName) = newData;
The newData may of course by a struct. The newFieldName must be string or character vector, which you may supply in a variable, e.g. varNames{i} as in your example.
Stephen23 on 14 Jan 2023
" there are many variables, and don't want to assign each variable to the structure without a loop."
That is a sign that your data design probably need to be improved. Instead of creating lots of separate variables, you should probably create one array in the first place. For example, if you are LOADing data from a MAT file, then simply LOAD into an output variable (which is a scalar structure):
S = load(..);
If you only have a handful of variables, then you could use a function like this (untested):
function S = mystruct(varargin)
S = struct();
for k = 1:nargin
S.(inputname(k)) = varargin{k};

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