Symbolic matrix operations without breaking it down to the element level.

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Martin 2018-3-23

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https://ww2.mathworks.cn/matlabcentral/answers/390163-symbolic-matrix-operations-without-breaking-it-down-to-the-element-level

Hi all, I want to check some derivations and gradients involving matrices and vectors and I would like to check it using the Symbolic Toolbox. But I do not want Matlab to break the matrix operations down on an element level since this blows up the equations and makes them almost impossible to read. For example I want the scalar product of a vector a with itself be displayed like this

a' * a

since there is nothing more to simplify. But if I use scalar symbolic variables I get

>> a = sym('a', 'real');
>> a' * a
ans =
a^2

which is not true if a is vector and if I use vectors of symbolic variables I get

>> a = sym('a', [3, 1], 'real');
>> a' * a
ans =
a1^2 + a2^2 + a3^2

which is hard to read in complex equations. I basically want Matlab to NOT break vectors and matrices down to their elements, just like a human would do, when deriving stuff on paper.

Is this possible? Thanks in advance.