RosettaCodeData/Task/Matrix-multiplication/Go/matrix-multiplication-3.go

61 lines
1.3 KiB
Go

package main
import "fmt"
type Value float64
type Matrix [][]Value
func Multiply(m1, m2 Matrix) (m3 Matrix, ok bool) {
rows, cols, extra := len(m1), len(m2[0]), len(m2)
if len(m1[0]) != extra {
return nil, false
}
m3 = make(Matrix, rows)
for i := 0; i < rows; i++ {
m3[i] = make([]Value, cols)
for j := 0; j < cols; j++ {
for k := 0; k < extra; k++ {
m3[i][j] += m1[i][k] * m2[k][j]
}
}
}
return m3, true
}
func (m Matrix) String() string {
rows := len(m)
cols := len(m[0])
out := "["
for r := 0; r < rows; r++ {
if r > 0 {
out += ",\n "
}
out += "[ "
for c := 0; c < cols; c++ {
if c > 0 {
out += ", "
}
out += fmt.Sprintf("%7.3f", m[r][c])
}
out += " ]"
}
out += "]"
return out
}
func main() {
A := Matrix{[]Value{1, 2, 3, 4},
[]Value{5, 6, 7, 8}}
B := Matrix{[]Value{1, 2, 3},
[]Value{4, 5, 6},
[]Value{7, 8, 9},
[]Value{10, 11, 12}}
P, ok := Multiply(A, B)
if !ok {
panic("Invalid dimensions")
}
fmt.Printf("Matrix A:\n%s\n\n", A)
fmt.Printf("Matrix B:\n%s\n\n", B)
fmt.Printf("Product of A and B:\n%s\n\n", P)
}