Question

我有一个函数来计算每个2D矩阵行与矩阵中第一行的余弦相似度。然后将每行的余弦相似度添加到称为激活的arraylist中。

以下是代码：

 List <Double> probeVectorList = new ArrayList <Double>();
 Double[] probeVectorArr = new Double[countMatrix2[0].length];
 List <Double> contextVectorList = new ArrayList <Double>();
 Double[] contextVectorArr = new Double[countMatrix2[0].length];
 List <Double> activation = new ArrayList <Double>();

 //display matrix
 for (int i = 0; i < countMatrix2.length; i++) {

    System.out.print(arrKeyWords[i]+"   "); //print keywords

    for (int j = 0; j < countMatrix2[0].length; j++) { 

         if (i==0)
         {
             probeVectorList.add(RoundTo2Decimals(contextVector[i][j])); //set the first row as probe vector
             probeVectorArr = probeVectorList.toArray(new Double[0]);
         }

            System.out.print(RoundTo2Decimals(contextVector[i][j])+", "); //print the entire matrix with rounded decimals

            //compute activation
           contextVectorList.add(RoundTo2Decimals(contextVector[i][j])); //here, in every iteration, the rows will be added into the list
           contextVectorArr = contextVectorList.toArray(new Double[0]); //convert list to array

           activation.add(cosineSimilarity(probeVectorArr, contextVectorArr)); //compute cosine similarity between the first row(static) and the subsequent row (cosineSimilarity function will take in 2 vector as input)

             } 

           //array out of bounds exception appears when attempting to calculate cosine similarity whenever I empty the array/list to make way for new rows 
          Arrays.fill(contextVectorArr, null); //empty array to make way for new rows
          contextVectorList.clear(); //empty list to make way for new rows

          System.out.println(" "); 
       }

根据评论建议，每当我尝试清空列表以便为下一行腾出时，它就会在Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1行显示activation.add(cosineSimilarity(probeVectorArr, contextVectorArr));。如果我不清空它将会正常工作，这将导致每一行都被添加到列表中。（矩阵包含每行相同的列数）...

任何人都可以提供帮助？谢谢！

Answer 1

使用空列表开始每次迭代，您的contextVectorList以及派生的contextVectorArr包含恰好一行的行：

contextVectorList.add(RoundTo2Decimals(contextVector[i][j]));

因此，索引1确实超出了范围。

在尝试在循环中清空arraylist时，数组超出范围

1 个答案: