Strassen's Matrix Multiplication Code In C

22 Sep, 2021

Int main. C Program to Implement the Schonhage-Strassen Algorithm for Multiplication of Two Numbers.

Strassen S Matrix Multiplication

Printf nAfter multiplication using n.

Strassen's matrix multiplication code in c. Printf Enter the 4 elements of first matrix. Void add int a int b int sizeint c. Partition b into four sub matrices b11 b12 b21 b22.

The above strategy is the basic O N3 strategy. The Strassen algorithm has a time complexity of mathcal Onlog_27o1 approx cal On2807The idea is similar to the Karatsuba. For int i 0.

Foriarai. This program calculates the multiplication of 2 matrices by Strassens Multiplication method. MatrixMultiplya b n arows let c be a new n x n matrix if n 1 c11 a11 b11 else partition a b and c C 11 MatrixMultiplyA 11 B 11 MatrixMultiplyA 12 B 21 C 1 2 MatrixMultiplyA 11 B 12 MatrixMultiplyA 12 B 22 C 2 1 MatrixMultiplyA 21 B 11 MatrixMultiplyA 22 B 21 C 22 MatrixMultiplyA 21 B 12 MatrixMultiplyA 22 B 22 return c.

We define a 3 arrays. Void sub int a int b int. Int a 2 2b 2 2c 2 2ij.

In practice the Schonhage-Strassen algorithm starts to outperform older. 1 The constants used in Strassens method are high and for a typical application Naive method works better. M7 a 0 1-a 1 1 b 1 0b 1 1.

M6 a 1 0-a 0 0 b 0 0b 0 1. Else Partition a into four sub matrices a11 a12 a21 a22. A b c all of int type.

Set Aa k void setmat A corners a datatype k int ij. This is a program to compute product of two matrices using Strassen Multiplication algorithm. After learning Data Structure and Algorithm Analysis C Version Third Edition 1633 STRASSEN matrix multiplied algorithm flow use C to implement STRASSEN method to seek matrix multiplication.

As x new lld 2. Then the multiplication is calculated by using strassens method and the new multiplied matrix is printed on the screen. The SchonhageStrassen algorithm is an asymptotically fast multiplication algorithm for large integers.

The usual matrix multiplication of two n times n matrices has a time-complexity of mathcalOn3This means if n doubles the time for the computation increases by a factor of 8. Algorithm Strassenn a b d begin If n threshold then compute C a b is a conventional matrix. Foriarai.

For two 22 matrices a and b where A. Else ifposition2 fori0iMatrixijn2. The number of rows columns are made fix to 2.

Strassen Matrix Multiplication program in c. Refer to this blog ideaAdd a link description. This C program implements Strassens algorithm to multiply two matrices.

Ifposition1 fori0iMatrixij. Set Aa randomlh. Matrix C aebg afbh cedg cfdh.

Here is the source code of the C program to multiply 22 matrices using Strassens. Consider two matrices A and B with 4x4 dimension each as shown below The matrix multiplication of the above two matrices A and B is Matrix C where c11 a11 b11 a12 b21 a13 b31 a14 b41 1 c 11 a 11 b 11 a 12 b 21 a 13 b 31 a 14 b 41 1. Schonhage-Strassen Algorithm is used to multiply two numbers.

First compute the following seven matrices. For int y 0. Foriarai.

Lld As new lld 2. Strassens insight was that we dont actually need 8 recursive calls to complete this process. But you dont have to use that much resources.

T N 7T N2 O N 2 From Masters Theorem time complexity of above method is O N Log7 which is approximately O N 28074 Generally Strassens Method is not preferred for practical applications for following reasons. Include include int divideint Matrixint nint position int ij. Algorithm for Strassens matrix multiplication.

Divide the matrix then use the Strassens formulae. C code of two 2 by 2 matrix multiplication using Strassen algorithm. For int j 0.

Here the dimensions of matrices must be a power of 2. Strassen algorithm is a recursive method for matrix multiplication where we divide the matrix into 4 sub-matrices of dimensions n2 x n2 in each recursive step. C Server Side Programming Programming.

Int adjM m 1 m. Strassens Algorithm is based on observing that XP YR XQ YS ZP WR and ZQ WS can be computed with only seven instead of eight as in Algorithm MMDC matrix multiplication operations as follows. P 1 XQ S P 2 X YS P 3 Z WP P 4 WRP P 5 X WP S P 6 Y WR S P 7 X ZP Q.

Fori0i. Divide and Conquer Method. Set Aa I void identitymat A corners a int ij.

As x y i new lld adjL. As x y new lld adjN. Using the Master Theorem with T n 8T n2 O n2 we still get a runtime of O n3.

All 3 are input by the user. Void randkmat A corners a double l double h int ij. Else ifposition3 fori0iMatrix.

For int x 0.

2 9 Strassens Matrix Multiplication Youtube

Project 3 Part B Project Description In This Project Chegg Com

Algorithm Divide And Conquer And Recursion Three Kinds Of Matrix Multiplication Brute Force Method Naive Divide And Conquer Method Strassen Method Programmer Sought