错误：调用期间未分配输出参数

Question

这是我的 k 最近邻算法代码：

function [preds, distances, indices] = knnfull(HandTrain,HandTest)
    nn_value = 10; % how many nearest      
    inputs = HandTrain(:,2:end);
    Y = HandTrain(:,1); 
    [preds, distances, indices] = knn_alg(inputs, y, HandTest, nn_value);
end

function [preds, D, I] = knn_alg(train_inputs, train_y, test_inputs, nn_value)
    num_train_inputs = size(train_inputs,2);
    num_train_examples = size(train_inputs,1)
    num_test_inputs = size(test_inputs,2);
    num_test_examples = size(test_inputs,1)
    preds = zeros(size(test_inputs,1),1);
    [D,I] = pdist2(train_inputs,test_inputs,'euclidean','Smallest',nn_value);
    preds = mode(train_y(I'),2);
end

如果你问我为什么有两个独立的函数，这是一个很好的问题。但无论如何，我得到了错误：

Error in knnkaggle>knn_alg (line 16)
num_train_inputs = size(train_inputs,2);

Output argument "indices" (and maybe others) not assigned during call to
"C:...knn_alg".

Error in knnkaggle (line 10)
[preds, distances, indices] = knn_alg(inputs, y, HandTest, nn_value);


无法解决问题。

Answer 1

这意味着通过您的函数的可能路径根本不为输出参数分配任何值。