Matrix Primer
Add two 3x3 matrices
Pre-conditions: two non-empty 3x3 matrices of integer/ real / complex type
Post-conditions: a new 3x3 matrix of the same type with the elements added
Pseudo-code:
1. Let the matrices A, B be the input matrices
2. Let the matrix holding the sum be called Sum.
3. For I in 1.. 3 loop
i. For J in 1.. 3 loop
1. Sum(I,J) := A(I,J) + B(I,J)
4. Return matrix Sum
Multiply two 3x3 matrices
Suppose that A and B are two matrices and that A is an m x n matrix (m rows and n
columns) and that B is a p x q matrix. To be able to multiply A and B together, A must
have the same number of columns as B has rows (i.e., n=p). The product will be a matrix
with m rows and q columns. To find the entry in row r and column c of the new matrix
we take the "dot product" of row r of matrix A and column c of matrix B (pair up the
elements of row r with column c, multiply these pairs together individually, and then add
their products).
Mathematically,
n
C(I,J) = ∑ A(I,K) B(K,J)
K=1
Where
I ranges from 1.. m
J ranges from 1.. q
K ranges from 1.. n = p
Pre-conditions: two non-empty 3x3 matrices of integer/ real / complex type
Post-conditions: a new 3x3 matrix of the same type with the product of the matrices
Pseudo-code:
1. Let the matrices A, B be the input matrices
2. Let the matrix holding the product be called Product.
3. Use a local variable sum to store the intermediate value of product.
4. For I in 1.. 3 loop
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