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Multiplication of two fields in a structure array

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SS
SS on 15 Jan 2020
Commented: SS on 16 Jan 2020
Hi. I want to perform element wise multiplication of two fields in a struture array. The size of the fields is same throughout for a given Struct(i). When, I use the code below it gives the following error:
"Argument to dynamic structure reference must evaluate to a valid field name"
for i=1:length(Struct)
Struct(i).dx_dc1=(Struct(i).L1).*(cos(Struct(i).phi1));
Struct(i).dy_dc=(Struct(i).L1).*(sin(Struct.(i).phi1));
Struct(i).dx_dc2=(Struct(i).L2).*(cos(Struct(i).phi2));
Struct(i).dz_dc=(Struct(i).L2).*(sin(Struct(i).phi2));
end

  2 Comments

Guillaume
Guillaume on 15 Jan 2020
Are you sure that it's the exact code with no modification that you're running?
This code doesn't have any dynamic structure reference so it would be very surprising for you to get the error stated. Now, if you had something like:
Struct(i).(something) %brackets around something make it a dynamic struct ref
then yes, you could get this type of error.

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Accepted Answer

Steven Lord
Steven Lord on 15 Jan 2020
You made a typo on this line.
Struct(i).dy_dc=(Struct(i).L1).*(sin(Struct.(i).phi1));
There shouldn't be a period between Struct and (i) in the sin call.
Struct(i).dy_dc=(Struct(i).L1).*(sin(Struct(i).phi1));

  2 Comments

Guillaume
Guillaume on 15 Jan 2020
Well spotted! This is indeed the dynamic struct ref.

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