strassens_algorithm (432B)
1 # Strassen's algorithm 2 3 https://en.wikipedia.org/wiki/Strassen_algorithm 4 5 multiplication of 2 by 2 matrices can be done with 7 products instead of 8 6 - gives an algorithm because you can reapply it recursively 7 8 works with integers, but not with [matrix_boolean] in [boolean_semiring] (or not as-is) 9 10 uses [subtraction], so works in a [ring] but not in a [semiring]: it is not a [combinatorial_algorithm] 11 12 Up: [matrix_multiplication]