MATLAB 矩阵转化为灰度图

A=[
1.00	0.96	0.98	0.88	0.94	0.61	0.96	0.80	0.98	0.89
0.96	1.00	0.94	0.90	0.95	0.71	0.96	0.83	0.90	0.88
0.98	0.94	1.00	0.84	0.91	0.54	0.93	0.73	0.97	0.90
0.88	0.90	0.84	1.00	0.89	0.85	0.94	0.94	0.80	0.82
0.94	0.95	0.91	0.89	1.00	0.72	0.94	0.84	0.90	0.90
0.61	0.71	0.54	0.85	0.72	1.00	0.74	0.90	0.48	0.64
0.96	0.96	0.93	0.94	0.94	0.74	1.00	0.90	0.92	0.87
0.80	0.83	0.73	0.94	0.84	0.90	0.90	1.00	0.70	0.75
0.98	0.90	0.97	0.80	0.90	0.48	0.92	0.70	1.00	0.85
0.89	0.88	0.90	0.82	0.90	0.64	0.87	0.75	0.85	1.00];
mat = A;           %# A n-by-n matrix of random values from 0 to 1
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(:),'%0.2f');  %# Create strings from the matrix values
textStrings = strtrim(cellstr(textStrings));  %# Remove any space padding
[x,y] = meshgrid(1:10);   %# Create x and y coordinates for the strings，it should be set based on the number of labels.
hStrings = text(x(:),y(:),textStrings(:),...      %# Plot the strings
                'HorizontalAlignment','center');
midValue = mean(get(gca,'CLim'));  %# Get the middle value of the color range
set(gca,'XTick',1:10,...                         %# Change the axes tick marks
        'XTickLabel',{'能源','材料','工业','可选消费','日常消费','医疗保健','金融','信息技术','电信服务','公共事业'},...  %#   and tick labels
        'YTick',1:10,...
        'YTickLabel',{'能源','材料','工业','可选消费','日常消费','医疗保健','金融','信息技术','电信服务','公共事业'},...
        'TickLength',[0 0]);
[x,y] = meshgrid(1:10);   %# 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