How to assign elements in a vector to an entry in a structure array variable?

I have an Nx1 structure array which contains a variable:

N = 100;
S(1).Name = 'Jon';
S(2).Name = 'Phil';
S(3).Name = 'Bob';
%etc...
S(N).Name = 'Gary';

I now have an Mx1 vector of values with associated indices which I want to add to a new variable within the structure:

vec = [36 39 21 74];
indices = [6 2 100 17];

S(1).('Age') = []; %initialize new variable in the structure

S(indices).Age = vec; %This is the intuition for what I want to do

However, this gives an error "Assigning to M elements using a simple assignment statement is not supported".

What I want to end up with is:

S(6).Age = 36;
S(2).Age = 39;
S(100).Age = 21;
S(17).Age = 74;

Of course, I could do this with a loop:

for i = 1:length(vec)
    S(indices(i)).Age = vec(i);
end

But I want to avoid loops because my code is already within another large loop which is slow.

Any help is appreciated.

Answer 1

[Matt J]

But I want to avoid loops because my code is already within another large loop which is slow.

When dealing with structs, there is no way to improve upon the speed of a loop. However, you can abbreviate the syntax as follows,

vals=num2cell(vec);

[S(indices).Age] = deal(vals{:});

Answer 2

[Matt J]

You could also consider using dictionaries instead of a struct array,

Names=["Jon","Phil","Bob","Gary"];

D=dictionary(Names,nan)

D = 
  dictionary (string ⟼ double) with 4 entries:

    "Jon"  ⟼ NaN
    "Phil" ⟼ NaN
    "Bob"  ⟼ NaN
    "Gary" ⟼ NaN

vec = [36  74];
indices = [1,4];

D(Names(indices))=vec

D = 
  dictionary (string ⟼ double) with 4 entries:

    "Jon"  ⟼ 36
    "Phil" ⟼ NaN
    "Bob"  ⟼ NaN
    "Gary" ⟼ 74

Answer 3

[Matt J]

You could also consider using a table instead,

Names=["Jon","Phil","Bob","Gary"]';

T=table(Names,nan(size(Names)), 'Var',["Name", "Age"])

T = 4×2 table
     Name     Age
    ______    ___

    "Jon"     NaN
    "Phil"    NaN
    "Bob"     NaN
    "Gary"    NaN

vec = [36  74]';
indices = [1,4]';

T{indices,"Age"}=vec

T = 4×2 table
     Name     Age
    ______    ___

    "Jon"      36
    "Phil"    NaN
    "Bob"     NaN
    "Gary"     74

This can then be converted to a struct array, if desired,

S=table2struct(T)

S = 4×1 struct array with fields:
    Name
    Age