用plot,hist等函数画各种图示

hist函数，给定一堆数据，统计数据在某一值的个数。plot是给定横/纵坐标向量，描绘点列。

统计频率---hist
第一步：用load导入文本数据，Matlab会自动生成以文件名命名的二维矩阵;
第二步：按列或按行取出所需要的数据，保存到变量；
第三步：添加标注文本。

保存为histogram.m%step1 load filefilename = 'dragon.nf1500k_2.m.txt';data = load(filename);%step2 retrieve relevant data freqOfGH = data(:,3);%step3 adjust the range of x,y range and draw histgramxRange=1:0.06:2.4;%for controlling the number of barsclf;set(gcf,'Color','w');hist(freqOfGH, xRange);%step4 set annotating informationaxis([1,2.2,0,400]);%h = findobj(gca,'Type','patch');set(h,'FaceColor',[1 0.76 0.05],'EdgeColor','w');xlabel('Average times for running the GH algorithm', 'fontsize',12,'fontweight','b');ylabel('Frequency', 'fontsize',12,'fontweight','b');%title(filename);datacursormode on %show datatip,right click to add/delete the datatip

显示一堆数据，并且画出拟合线---plot, polyfit
第一步：用load导入文本数据，Matlab会自动生成以文件名命名的二维矩阵;
第二步：按列或按行取出所需要的数据，保存到变量；
第三步：将横/纵坐标调整到合理的范围，利用上述得到的数据，plot, polyfit画图；
第四步：添加标注文本。

保存为fittingCurve.m%step1 loadfilename = 'dragon.nf100k_2.m.txt';data = load(filename);%load data from current folder %step2 retrieve relevant dataenclosingVertices = data(:,2);%retrieve the second column of data refiningSteps = data(:,4);%retrieve the fourth column of data %step3 customize background and plot%customize colorclr=[1 0.76 0.05];clf;set(gcf,'Color','b');%set the color of figure background%set the style and color of marker plot(enclosingVertices,refiningSteps,'m+','MarkerEdgeColor',clr);hold on;%for plotting another figure on the same figure%restrict the range of x-valuexAxis=0:max(enclosingVertices);%using polynormal(here we use linear) to fit the plotted dataP=polyfit(enclosingVertices,refiningSteps,1);plot(xAxis,polyval(P,xAxis),'r-', 'LineWidth',2);%step4 set annotating information axis([200,3600,0,230]);%restrict the range of x- and y-axisxlabel('The number of swept verticefs','fontsize',12,'fontweight','b');ylabel('The number of evolving steps','fontsize',12,'fontweight','b');equation='y=0.05x+4.68';text(2300,110,equation,'fontsize',11,'fontweight','b');legend('Pair(m, steps)',equation);title('Sample Figure','fontsize',12,'fontweight','b');hold off;

y扫描线上，画颜色各通道的Intensity值
第一步：导入数据，imread;
第二步：取得三个通道的值，并分别保存到三个独立的变量中r,g,b;
第三步：由于真彩色图像三个通道的颜色值在0-255范围内，而且是无符号整型。故需将它们转换到0-1的double型，作为各通道的强度值；
第四步：在同一个Figure上，沿着一条y扫描线，将该扫描线上各通道的值画出来。注意，plot的两个参数需要的是向量。
%step1 read imagergb=imread('Water lilies.jpg');%step2 retrieve relevant data and show imagesr=rgb(:,:,1);%r chanel,range 0-255subplot(2,2,1),imshow(r);title('R channel');g=rgb(:,:,2);%g chanel,range 0-255subplot(2,2,2),imshow(g);title('G channel');b=rgb(:,:,3);%b chanel,range 0-255subplot(2,2,3),imshow(b);title('B channel');%step3 scale value of r,g,b channel to intensity(0-1)I1=double(r)./255;%intensity of channel r,range 0-1,doubleI2=double(g)./255;%intensity of channel g,range 0-1,doubleI3=double(b)./255;%intensity of channel b,range 0-1,double%step4 plot the intensity along the image's width- y-scan line[w,h,n]=size(rgb);%get the width and height of the imagescanline=100;%customize the ?th y-scanline,it is within 0-wx=1:h;% x-axis for function plotI1_sl=I1(scanline,:);%y-axis for function plotI2_sl=I2(scanline,:);%y-axis for function plotI3_sl=I3(scanline,:);%y-axis for function plotsubplot(2,2,4),plot(x,I1_sl,'-r',x,I2_sl,'-g',x,I3_sl,'-b');%step5 add annotating informationxlabel('y-coordinate[px]');ylabel('signal intensity');legend('R channel', 'G chnanel', 'B channel','Location','NorthWe