Analysis of Algorithms : An Active Learning Approach

(Ron) #1
RESULTS OF CHAPTER STUDY SUGGESTIONS 271

Preprocessed Coefficients

Standard Matrix Multiplication

Winograd’s Matrix Multiplication
Row factors: 4 40
Column factors: 18 14
Strassen’s Algorithm
x 1 = (G1,1 + G2,2)* (H1,1 + H2,2) = (1 + 8) * (6 + 2) = 9 * 8 = 72
x 2 = (G2,1 + G2,2)*H1,1 = (5 + 8) * 6 = 13 * 6 = 78
x 3 = G1,1* (H1,2H2,2) = 1 * (7  2) = 1 * 5 = 5
x 4 = G2,2* (H2,1H1,1) = 8 * (3  6) = 8 *3 =  24
x 5 = (G1,1 + G1,2)*H2,2 = (1 + 4) * 2 = 5 * 2 = 10
x 6 = (G2,1G1,1)* (H1,1 + H1,2) = (5  1) * (6 + 7) = 4 * 13 = 52

x 7 = (G1,2G2,2) (H2,1 + H2,2) = (4  8) (3 + 2) =  (^4) 5 =  20
R1,1 = x 1 + x 4 x 5 + x 7 = 72 +  24  10 + 20 = 18
R2,1 = x 2 + x 4 = 78 + 24 = 54
R1,2 = x 3 + x 5 = 5 + 10 = 15
R2,2 = x 1 + x 3 x 2 + x 6 = 72 + 5  78 + 52 = 51
) x^7  8 x^6  3 x^5  2 x^4  4 x^3  00 x^2  05 x 07
x^7  8 x^6  3 x^5  2 x^4  5 x^3  40 x^2  15 x 10
x^3  40 x^2  20 x 03
x^3  08 x^2  03 x 02
x^4  5
[]()x^4 – (^5)
()x^3 – 8 x^2 ++ 3 x 2 +()x^3 – 40 x^2 ++ 20 x 3
x 08
) x (^3)  8 x (^2)  3 x 02 )
x^3  8 x^2  2 x 16
x^2  2
x 18
x^3  40 x^2  20 x 003
x 040
x^3  40 x^2  19 x 760
x^2  19
x 757
[]()x^4 – (^5) ()[]()x^2 + (^2) ()x– 8 +()x+ 18 +{}[]()x^2 + (^19) ()x– 40 +()x+ 757
14
58
67
32
(^1643)
+ (^1742) +
(^5683)
+ (^5782) + *
18 15
54 51

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