Issue No. 10 - October (1973 vol. 22)
H.Y.L. Mar , Department of Electrical Engineering, University of Ottawa
For the Hadamard matrix, a modified factorization procedure is developed that is likely as economical in storage requirements and in the number of computational operations as the conventional fast Hadamard transform. Using this specific factoring method, the procedure for obtaining the fast Hadamard transform may be interpreted as operations on an H diagram. The H diagram was originally derived by Marihugh and Anderson  to provide a graphical representation for logic functions.
Fast Hadamard transform, H diagram, Hadamard matrix, Hadamard transform, hypercube, Kronecker product, matrix factorization, spectral coefficients.
C.L. Sheng, H.Y.L. Mar, "Fast Hadamard Transform Using the H Diagram", IEEE Transactions on Computers, vol. 22, no. , pp. 957-960, October 1973, doi:10.1109/T-C.1973.223624