Gram Matrix

I thought Gram Matrix should be in the form of X^TX and each of its element is the dot product of two vectors.

The Style Matrix in this video doesn’t look like a normal Gram Matrix in my mind. The correlation between two matrics is a scaler G^{[l]}_{k,k'}. Is it also a kind of Gram Matrix?

The style matrix we compute is a correlation matrix of the form X^T \cdot X. It’s been a long time since I watched those lectures and if it makes our heads hurt to parse all the subscripts there to try to map that to the implied matrix multiplication, please “stay tuned” and watch what happens when you implement this in the assignment.