矩阵的标量乘法程序 · GeeksForGeeks 中文系列教程

# 矩阵的标量乘法程序 > 原文： [https://www.geeksforgeeks.org/program-for-scalar-multiplication-of-a-matrix/](https://www.geeksforgeeks.org/program-for-scalar-multiplication-of-a-matrix/) 给定一个矩阵和一个标量元素 k，我们的任务是找出该矩阵的标量积。 **示例**： ``` Input : mat[][] = {{2, 3} {5, 4}} k = 5 Output : 10 15 25 20 We multiply 5 with every element. Input : 1 2 3 4 5 6 7 8 9 k = 4 Output : 4 8 12 16 20 24 28 32 36 ``` 数为 k（标量）的**标量乘法**，将其乘以矩阵中的每个条目。矩阵 A 为矩阵 kA。 ## C++ ```cpp // C++ program to find the scalar product // of a matrix #include <bits/stdc++.h> using namespace std; // Size of given matrix #define N 3 void scalarProductMat(int mat[][N], int k) { // scalar element is multiplied by the matrix for (int i = 0; i < N; i++) for (int j = 0; j < N; j++) mat[i][j] = mat[i][j] * k; } // Driver code int main() { int mat[N][N] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } }; int k = 4; scalarProductMat(mat, k); // to display the resultant matrix printf("Scalar Product Matrix is : \n"); for (int i = 0; i < N; i++) { for (int j = 0; j < N; j++) printf("%d ", mat[i][j]); printf("\n"); } return 0; } ``` ## Java ```java // Java program to find // the scalar product // of a matrix import java.io.*; class GFG { static final int N = 3; static void scalarProductMat(int mat[][], int k) { // scalar element is multiplied // by the matrix for (int i = 0; i < N; i++) for (int j = 0; j < N; j++) mat[i][j] = mat[i][j] * k; } // Driver code public static void main (String[] args) { int mat[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } }; int k = 4; scalarProductMat(mat, k); // to display the resultant matrix System.out.println("Scalar Product Matrix is : "); for (int i = 0; i < N; i++) { for (int j = 0; j < N; j++) System.out.print(mat[i][j] + " "); System.out.println(); } } } // This code is contributed by Ajit. ``` ## Python 3 ``` # Python 3 program to find the scalar # product of a matrix # Size of given matrix N = 3 def scalarProductMat( mat, k): # scalar element is multiplied # by the matrix for i in range( N): for j in range( N): mat[i][j] = mat[i][j] * k # Driver code if __name__ == "__main__": mat = [[ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ]] k = 4 scalarProductMat(mat, k) # to display the resultant matrix print("Scalar Product Matrix is : ") for i in range(N): for j in range(N): print(mat[i][j], end = " ") print() # This code is contributed by ita_c ``` ## C# ```cs // C# program to find // the scalar product // of a matrix using System; class GFG{ static int N = 3; static void scalarProductMat(int[,] mat, int k) { // scalar element is multiplied // by the matrix for (int i = 0; i < N; i++) for (int j = 0; j < N; j++) mat[i,j] = mat[i, j] * k; } // Driver code static public void Main () { int[,] mat = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}; int k = 4; scalarProductMat(mat, k); // to display the resultant matrix Console.WriteLine("Scalar Product Matrix is : "); for (int i = 0; i < N; i++) { for (int j = 0; j < N; j++) Console.Write(mat[i, j] + " "); Console.WriteLine(); } } } // This code is contributed by Ajit. ``` ## PHP ```php <?php // PHP program to find // the scalar product // of a matrix function scalarProductMat($mat, $k) { $N = 3; // scalar element is multiplied // by the matrix for ( $i = 0; $i < $N; $i++) for ($j = 0; $j < $N; $j++) $mat[$i][$j] = $mat[$i][$j] * $k; return $mat; } // Driver code $N = 3; $mat = array(array(1, 2, 3 ), array( 4, 5, 6 ), array(7, 8, 9 )); $k = 4; $mat1 = scalarProductMat($mat, $k); // to display the resultant matrix echo("Scalar Product Matrix is : " . "\n"); for ($i = 0; $i < $N; $i++) { for ($j = 0; $j < $N; $j++) echo($mat1[$i][$j] . " "); echo "\n"; } // This code is contributed // by Mukul Singh ``` **输出**： ``` Scalar Product Matrix is : 4 8 12 16 20 24 28 32 36 ``` * * * * * *