MATLAB中的混淆矩阵的实现

混淆矩阵的matlab代码实现：

actual：就是我们已知的label。

detected是我们通过模型预测得到的label

结合下面语句实现：

 [pred,acc,preb] = svmpredict(double(testLabel), testData, model, '-b 1');

 function confusion_matrix(actual,detected)
 [mat,order] = confusionmat(actual,detected);

 %mat = rand(10);           %# A 5-by-5 matrix of random values from 0 to 1
% mat(3,3) = 0;            %# To illustrate
% mat(5,2) = 0;            %# To illustrate
imagesc(mat);            %# Create a colored plot of the matrix values
colormap(flipud(gray));  %# Change the colormap to gray (so higher values are
                         %#   black and lower values are white)

textStrings = num2str(mat(:),'%0.02f');  %# Create strings from the matrix values
textStrings = strtrim(cellstr(textStrings));  %# Remove any space padding

%% ## New code: ###
%idx = find(strcmp(textStrings(:), '0.00'));
%textStrings(idx) = {'   '};
%% ################

[x,y] = meshgrid(1:5);   %# Create x and y coordinates for the strings
hStrings = text(x(:),y(:),textStrings(:),...      %# Plot the strings
                'HorizontalAlignment','center');
midValue = mean(get(gca,'CLim'));  %# Get the middle value of the color range
textColors = repmat(mat(:) > midValue,1,3);  %# Choose white or black for the
                                             %#   text color of the strings so
                                             %#   they can be easily seen over
                                             %#   the background color
set(hStrings,{'Color'},num2cell(textColors,2));  %# Change the text colors

set(gca,'XTick',1:5,...                         %# Change the axes tick marks
        'XTickLabel',{'Bob','Hyt','Maple','Study','Zm'},...  %#   and tick labels
        'YTick',1:5,...
        'YTickLabel',{'Bob','Hyt','Maple','Study','Zm'},...
        'TickLength',[0 0]);

结果是：