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[Coder] Which types are supported for constant folding?

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In MATLAB HDL coder I try to do constant folding on the output of a function.
The output type is a 1x262144 uint16.
The coder complains with:
The input to coder.const cannot be reduced to a constant: Unsupported type.
Which types are supported?
Jan Siegmund
Jan Siegmund on 18 Mar 2020
I found the matrix being responsible for the issue. It is created from a concatenation in a for loop.
However the size can be determined at compile time wihtout doubt.
I tried to help the coder with
coder.varsize('a', [1 2^b], [0 0])
where b is compile time constant, but it still complains, that it cannot create the vector from concatenation
if the size is locked. Is there any other way?

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Accepted Answer

Jan Siegmund
Jan Siegmund on 2 Apr 2020
I did understand constant folding wrong:
I thought one must help the coder as follows:
a = coder.const(my_prod(3,2));
, because the gui of the fixed point converter was still complaining about a unsupported function in
But the statement is already recognized as constant.
just needs to be used, if you call a function multiple times with different input parameters
and you want the coder to create the function multiple times, each time with all of the parameters constant.

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