我很难找到一种在二维数组中找到相邻值之和的好方法。我需要在索引位置找到所有相邻值的总和。如果位置是边缘，我需要将它的值转换为总和。因此，每个元素都有4个值对其总和有贡献。
实施例。
索引[0] [0] = 5.0的元素。 [0] [1] = 2，[1] [0] = 4.总和 index [0] [0] = 5（左/镜子本身）+5（向上/自身镜像）+ 2（右边）+4（低于它）= 16。
到目前为止，我的代码如下。建议更好的方式将不胜感激。此代码正在获取
ArrayOutOfBounds：3
在评论后的行上说// ERROR **
Public static double [][] getSumWeight(double [][] map){
int base = 0;
//int count = getEnhancementLevel();
int row = map.length;
int col = map[0].length;
int newRow = row*2;
int newCol = col*2;
double [] [] sumMap = new double [row][col];
double [][] weightMap = new double [newRow][newCol];
//getting the corner sum weights
for (int i = 0; i < map.length; i++){
for (int j = 0; j < map[i].length; j++){
if (i == 0 && j == 0){
double result = 0;
result += (map[0][0])*2;
result += map[0][1];
result += map[1][0];
sumMap[0][0] = result;
System.out.println("corner" + sumMap[0][0]);
}
else if (i == 0 && j == map[0].length){
double result = 0;
result += map[0][map[0].length];
result += map[0][map[0].length-1];
result += map[1][map[0].length];
sumMap[i][j] = result;
}else if (i == map.length && j == 0){
}else if (i == map.length && j == map[map.length].length){
}
//getting the mid(s) of the top row
else if (i == 0 && j != 0 && j != map[0].length){
double result = 0;
result += map[i][j]; //top value or mirror
result += map[i][j-1]; // left value
//ERROR****
result += map[i][j+1]; // right value
result += map[i+1][j]; // bottom value
sumMap[i][j] = result;
}
//getting the mid(s) of the bottom row
else if (i == map.length && j != 0 && j != map[map.length].length){
double result = 0;
result += map[i][j];
result += map[i][j-1];
result += map[i][j+1];
result += map[i-1][j];
sumMap[i][j] = result;
}
//getting the mid(s) of the left most column
else if (j == 0 && i != 0 && i != map.length){
double result = 0;
result += map[i][j];
result += map[i-1][j];
result += map[i+1][j];
result += map[i][j+1];
sumMap[i][j] = result;
}
//getting the mid(s) of the right most column
else if (j == map[0].length && i != 0 && i != map.length){
double result = 0;
result += map[i][j];
result += map[i-1][j];
result += map[i+1][j];
result += map[i][j-1];
sumMap[i][j] = result;
}
//filling in all the remaining values
else{
double result = 0;
result += map[i-1][j];
result += map[i+1][j];
result += map[i][j-1];
result += map[i][j+1];
sumMap[i][j] = result;
}
}
}
for (int i = 0; i < map.length; i++){
for (int j = 0; j < map[i].length; j++){
System.out.println(sumMap[i][j]);
}}
return sumMap;
}
答案 0 :(得分：1)
**//The function receives a matrix and replaces each value in the matrix with the value of the sum of its neighbors
public static int[][] sumOfNeighbours(int[][] mat) {
int[][] sum = new int[mat.length][mat[0].length];
for (int i = 0; i < mat.length; i++) {
for (int j = 0; j < mat[i].length; j++) {
if (i == 0) {
if (j == 0) {
sum[i][j] = mat[i + 1][j + 1] + mat[i][j + 1] + mat[i + 1][j];//dells with the top left corner
} else if (j == mat[i].length - 1) {
sum[i][j] = mat[i + 1][j - 1] + mat[i][j - 1] + mat[i + 1][j];//dells with the top right corner
} else {
sum[i][j] = mat[i][j - 1] + mat[i][j + 1] + mat[i + 1][j + 1] + mat[i + 1][j - 1] + mat[i + 1][j];//top middles
}
} else if (i == mat.length - 1) {
if (j == 0) {
sum[i][j] = mat[i - 1][j] + mat[i - 1][j + 1] + mat[i][j + 1];//dells with the bottom left corner
} else if (j == mat[i].length - 1) {
sum[i][j] = mat[i - 1][j] + mat[i][j - 1] + mat[i - 1][j - 1];//dells with the bottom right corner
} else {
sum[i][j] = mat[i - 1][j] + mat[i - 1][j - 1] + mat[i - 1][j + 1] + mat[i][j + 1] + mat[i][j - 1];//dells with the bottom middles
}
} else if (j == 0) {//first column
if ((i != 0) && (i != mat.length - 1))
sum[i][j] = mat[i - 1][j] + mat[i + 1][j] + mat[i + 1][j + 1] + mat[i - 1][j + 1] + mat[i][j + 1];//dells with the left middles
} else if (j == mat[i].length - 1) {//last column
if ((i != 0) && (i != mat.length - 1))
sum[i][j] = mat[i - 1][j] + mat[i + 1][j] + mat[i - 1][j - 1] + mat[i][j - 1] + mat[i + 1][j - 1];//dells with the right middles
} else {
sum[i][j] = mat[i][j - 1] + mat[i][j + 1] + mat[i + 1][j] + mat[i + 1][j - 1] + mat[i + 1][j + 1] + mat[i - 1][j] + mat[i - 1][j - 1] + mat[i - 1][j + 1];//dells with the all the rest
}
}
}
return sum;
}**
答案 1 :(得分：0)
你在行中得到一个ArrayOutOfBounds异常：
result += map[i][j+1]; // right value
因为你到达for循环中的最后一个位置map[i].length并访问下一个（越界）位置map[i][j+1];
请注意，您正在检查您是否错误地到达了最后一个位置：
Example: map[0].length = 4 (0,1,2,3)
else if (i == 0 && j != 0 && j != map[0].length){ // j=3 but j!=4
result += map[i][j+1] //<- error
}
你应该检查：
else if (i == 0 && j != 0 && j != (map[0].length -1)){
答案 2 :(得分：0)
这是您的解决方案。我知道有很多if else陈述，但这是我最好的。
for(int i=0;i<a.length;i++){
for(int j=0;j<a[i].length;j++){
if(i==0){
if(j==0){
sum[i][j] = a[i][j]*2 + a[i+1][j] + a[i][j+1];
}
else if(j==a[i].length-1){
sum[i][j] = a[i][j]*2 + a[i][j-1] + a[i+1][j] ;
}
else{
sum[i][j] = a[i][j] + a[i][j-1] + a[i+1][j] + a[i][j+1];
}
}
else if(i==a.length-1){
if(j==0){
sum[i][j] = a[i][j]*2 + a[i-1][j] + a[i][j+1];
}
else if(j==a[i].length-1){
sum[i][j] = a[i][j]*2 + a[i][j-1] + a[i-1][j] ;
}
else{
sum[i][j] = a[i][j] + a[i][j-1] + a[i-1][j] + a[i][j+1];
}
}
else if(j==0){
sum[i][j] = a[i][j] + a[i-1][j] + a[i+1][j] + a[i][j+1];
}
else if(j==a[i].length-1){
sum[i][j] = a[i][j] + a[i-1][j] + a[i+1][j] + a[i][j-1];
}
else{
sum[i][j] = a[i][j-1] + a[i-1][j] + a[i+1][j] + a[i][j+1];
}
}
}
答案 3 :(得分：0)
算法更加简单（我改变了第一个解决方案，因为我理解要求乍一看错误了要求）;所有的逻辑都在第一个。我主要摆脱了所有不必要的循环......
public class MatrixAlgoritm {
public static double[][] getSumWeight(double[][] map) {
int row = map.length;
int col = map[0].length;
double[][] sumMap = new double[row][col];
for (int i = 0; i < map.length; i++) {
for (int j = 0; j < map[i].length; j++) {
double result = 0;
result += map[Math.max(0, i - 1)][j];
if (i == map.length - 1) {
result += map[i][j];
} else {
result += map[i + 1][j];
}
result += map[i][Math.max(0, j - 1)];
if (j == map[0].length - 1) {
result += map[i][j];
} else {
result += map[i][j + 1];
}
sumMap[i][j] = result;
}
}
for (int i = 0; i < row; i++) {
for (int j = 0; j < col; j++) {
System.out.println(sumMap[i][j]);
}
}
return sumMap;
}
public static void main(String[] args) {
double[][] baseMap = {{2, 10, 7}, {4, 5, 8}, {5, 6, 9}};
getSumWeight(baseMap);
}
}
答案 4 :(得分：0)
算法非常简单
int sum[][] = new int[c][c];
for(int i = 0; i < arr.length; i++)
{
for(int j = 0; j < arr[i].length; j++)
{
int result = 0;
if(j > 0)
result += arr[i][j-1];
if(j < arr[i].length - 1)
result += arr[i][j+1];
if(i > 0)
result += arr[i-1][j];
if(i > 0 && j > 0)
result += arr[i-1][j-1];
if(i > 0 && j < arr[i].length - 1)
result += arr[i-1][j+1];
if(j > 0 && i < arr.length -1)
result += arr[i+1][j-1];
if(j < arr[i].length - 1 && i < arr.length -1)
result += arr[i+1][j+1];
if(i < arr.length -1)
result += arr[i+1][j];
sum[i][j] = result;
}
}