matlab - 如何解决 “Operands … must be convertible to logical scalar values” MATLAB错误消息？

Question

在MATLAB中运行代码时，总是会收到此错误消息。我想进行模板匹配以识别字符。

  ??? Operands to the || and && operators must be convertible to logical scalar values.

  Error in ==> readLetter at 17
  if vd==1 || vd==2

我的代码是

  load NewTemplates % Loads the templates of characters in the memory.
  gambar = imresize(gambar,[42 24]); % Resize the input image 
  comp = [];
  for n = 1 : length(NewTemplates)
      sem = corr2(NewTemplates{1,n}, gambar); % Correlation with every image in the template for best matching.
      comp = [comp sem]; % Record the value of correlation for each template's character.
  end

  vd = find(comp == max(comp)); % Find index of highest matched character.

  % According to the index assign to 'letter'.
  if vd==1 || vd==2
      letter='A';

如何解决？

Answer 1

当comp包含多个具有最大值的元素时，find()返回一个 vector 。

看到这个:

a = [1:5 5];
index = find(a==max(a)); % index =  5  6
numel(index) % ans = 2

因此，请使用max函数 而不是find 或仅使用第一个匹配项。