Question

我在课堂上把这个问题分配给了我。我还在学习MATLAB，所以我无法弄清楚如何使用索引来解决这个问题。问题是：给定一个数字的行向量，找到两个最接近的数字的索引。例如：

[index1 index2]=nearestNumbers([2 6 3 13 0 -16.1])
This would output:
index1 = 1
index2 = 3
Since the numbers 2 and 3 in the vector are closer to each other than 
any other pair of numbers

我猜我需要在这里使用find函数（在y = find(min())的某处），但我不确定如何将其转换为连贯的代码行。我尝试使用我提到的find函数，但它只给了我一个0的向量行。非常感谢您的帮助！

Answer 1

没有循环，只有bsxfun：

>> B = abs( bsxfun(@minus, A, A' ) ); %//'
>> B( 1: (numel(A)+1) : end ) = inf; % ignore zeros on diagonal
>> [ii jj] = find( B == min(B(:)) );

Answer 2

尝试为每个索引获取每个索引的距离函数。

for i=1:length(A)
   for j=1:i
      B(i,j)=NaN;
   end
   for j=i+1:length(A)
      B(i,j)=abs(A(i)-A(j));
   end
end

B =

       NaN    4.0000    1.0000   11.0000    2.0000   18.1000
       NaN       NaN    3.0000    7.0000    6.0000   22.1000
       NaN       NaN       NaN   10.0000    3.0000   19.1000
       NaN       NaN       NaN       NaN   13.0000   29.1000
       NaN       NaN       NaN       NaN       NaN   16.1000
       NaN       NaN       NaN       NaN       NaN       NaN

[ind1,in2]=find(B==min(min(B)))

ind1 =

ind2 =

MATLAB：给定行向量，找到两个最接近数字的索引

2 个答案: