MATLAB 操作總結(jié)

如何用命令行保存圖片？

1. saveas

??用法：saveas( fig, filename, formattype )

??Example:

    x = [2 4 5 6 7];
    bar(x);
    saveas( gcf, 'Barchart.png' )
    saveas( gcf, 'Barchart', 'epsc' ) % save figure as EPS file

2. print

?? 用法: print( filename, formattype, formatoptions )

??Example:

    % save figure as image file
    bar(1:10)
    print( 'BarPlot', '-dpng' )
    % copy figure to Clipboard
    plot(1:10)
    print( '-clipboard','dmeta' )
    

    fig = figure;
    plot(1:10);
    print( fig, 'MySaveplot', '-dpng' )

畫圖控制

用到的重要函數(shù)有 gca, gcf, set, text。
在需要的時(shí)候請(qǐng)仔細(xì)閱讀 MATLAB 中 Axes Properties 等相關(guān)文檔，了解圖形控制中可變參數(shù)。

函數(shù)說明:

• gca ?返回當(dāng)前坐標(biāo)軸和圖形。

    x = -2*pi:0.1:2*pi;
    y = sin(x);
    plot(x,y)
    xlabel('x')
    ylabel('y')
  
    ax = gca;
    ax.XAxisLocation
    ax.YAxisLocation
    ax.XAxisLocation = 'origin'; % setting x axis location to origin
    ax.YAxisLocation = 'origin'; % setting y axis location to origin
    ax.Box = 'off'; % Turn off the display of the axes outline
    ax.Layer = 'top'; % Make grid lines and tick marks appear over graphics objects
  

mf1.jpg

• gcf ?返回當(dāng)前圖形的句柄

    surf(peaks)
    fig = gcf;
    fig.Color = [0 0.5 0.5];
    fig.ToolBar = 'none';
  

mf2.jpg

• set ?設(shè)置圖形目標(biāo)性質(zhì)

  語(yǔ)法： set(H, Name, Value)

    x = 0:30;
    y = [1.5*cos(x); 4*exp(-.1*x).*cos(x); exp(.05*x).*cos(x)]';
    S = stem(x,y);
    NameArray = {'Marker','Tag'};
    ValueArray = {'o','Decaying Exponential';...
    'square','Growing Exponential';...
    '*','Steady State'};
    set(S,NameArray,ValueArray)
  

mf3.jpg

子圖控制

Colorbar控制

Position 參數(shù)為 [left bottom width height]

    x=[60:20:260]; %set x axis ticks
    y=rand(11);  %get something to plot
    h1=subplot(2,1,2); %setup subplot1
    plot(x,y,'-.'); %plot subplot1
    box on  %  leave only x and y axes
    xlim([60 260])  %setup some x axis 
    set(h1,'Xtick',x) %set the x axis ticks to show only x
    h1_pos = get(h1,'Position'); %get the position data for sublot1.
    y2 = 10*y.^2;  %make something up for subplot2
    h2=subplot(2,1,1);  %make subplot2
    plot(x,10*y,'-.'); %plot subplot2
    box on
    set(h2,'Xcolor',[1 1 1]) %make the Y axis line white
    set(h2,'Xtick',[])
    xlim([60 260])  %setup some x axis 
    h2_pos=get(h2,'Position'); 
    set(h2,'Position',[h1_pos(1) h1_pos(2)+h1_pos(4) h2_pos(3:end)]) %using position of subplot1 put subplot2next to it.

mf4.jpg

坐標(biāo)軸控制

1. 坐標(biāo)軸刻度朝外

   set(gca, 'tickdir', 'out')

2. 坐標(biāo)軸顏色

   set(gca, 'XColor', 'red')

3. 其它

    set(gca, 'XLim', [min max]);   % range 
    set(gca, 'XTick', [ markerpoint ]);     % markerpoint
    set(gca, 'XTicklabel', {}];     %marker
    set(gca, 'XGrid', 'on');        %grid on
   

防止圖縮小后字體過小或發(fā)虛

    set(gcf, 'Position', [100 100 260 220]);
    set(gca, 'Position', [.13 .17 .80 .74]);
    figure_Fontsize = 8;
    set(get(gca, 'XLabel'), 'FontSize', figure_Fontsize, 'Vertical', 'top');
    set(get(gca, 'YLabel'), 'FontSize', figure_Fontsize, 'Vertical', 'middle');
    set(findobj('FontSize',10), 'FontSize', figure_Fontsize);
    set(findobj(get(gca, 'Children'), 'LineWidth', 0.5), 'LineWidth', 2);

圖形窗口

colordef 定義繪圖背景色

隨機(jī)數(shù)生成

可用函數(shù): rand, randi, randn, randperm, randsrc, unifrnd