四课数据可视化ppt课件

1、第四课数据可视化v二维绘图v三维绘图v显示图像实验内容：用图形表示离散函数vn = 0:12;vy=1./abs(n+eps-6);vplot(n,y,r*,MarkerSize,20);vgrid on用图形表示延续函数v对延续函数进展离散化。v根本方法：采样。v采样密度。可视化的普通步骤v绘制二维图形v绘制三维图形实验内容：绘制二维图形v数据预备v选定图形窗或子图位置v调用绘图指令v设置显示值范围、刻度和坐标分格线v图形注释v图形的精细修饰数据预备v产生自变量的采样向量及定义域；v计算相应的函数值，相应得到值域。vmatlab：vt = pi*(0:100)/100;vy = sin(t)

2、.*sin(9*t);选定图形窗及子图位置v缺省窗口v用指令翻开指定图形窗口和子图号vmatlab：vfigure(1);vsubplot(2,2,3);调用绘图指令v线型v颜色v数据点vmatlab：vplot(t,y,b-)线型符号：.含义实线虚线点划线双划线颜色符号bgrcmykw含义蓝绿红青品红黄黑白数据点符号含义符号含义.实心黑点d菱形符diamond+十字符h六角星符hexagram*八线符o空心圆圈朝上三角符p五角星符pentagram朝右三角符x叉字符v朝下三角符设置显示值范围、刻度和坐标分格线vmatlab：vaxis(0,pi,-1,1);vgrid on;常用坐标指令一坐

3、标轴控制方式、取向和范围指令含义axis auto使用缺省设置axis manual当前坐标轴范围不变axis on使用轴背景axis off取消轴背景axis ij矩阵式坐标axis xy普通直角坐标axis(v)v=x1,x2,y1,y2手工设定坐标范围常用坐标指令二坐标轴的高宽比指令含义axis equal纵横轴等刻度axis fillmanual下使坐标充满绘图区axis image纵横轴等刻度，坐标框紧贴数据范围axis normal缺省矩形坐标系axis square产生正方形坐标系axis tight把数据范围直接设为数据范围图形注释vmatlab:vtitle(调制波形);vx

4、label(t); ylabel(y);vlegend(sin(t),sin(t)sin(9t);vtext(2,0.5,y=sin(t)sin(9t);图形的精细修饰vmatlab:vset(h,MarkerSize,10);叠绘vt = 2*pi*(0:20)/20;vy = cos(t).*exp(-0.4*t);vstem(t,y,g);vhold on;vstairs(t,y,r);vhold off;实验内容：绘制三维图形v三维数据预备：曲线和曲面v选定图形窗及子图位置v设置显示值范围、刻度和坐标分格线v图形注释v着色、明暗、灯光和材质处置v视点、三度纵横高比绘制三维曲线vmatl

5、ab:vt = pi*(0:0.02:2);vx = sin(t); y=cos(t); z = cos(2*t);vplot3(x,y,z,b-,x,y,z,bd);vview(-82,58), box on, legend(链,宝石);绘制三维曲面vmatlab:vx = -10:0.1:10;vy = -10:0.1:10;vX,Y = meshgrid(x,y);vZ = X.2+Y.2;vmesh(Z);根本三维绘图指令v曲线：vplot3v曲面：vmeshvsurfvstem3vn = 0:0.1:12;vy = 1./abs(n+eps-6);vh = plot(n,y,r*,M

6、arkerSize,20);vgrid onv vtitle(调制波形);vxlabel(t); ylabel(y);vlegend(sin(t)sin(9t);vtext(2,0.5,y=sin(t)sin(9t);v vset(h,MarkerSize,10);vt = 2*pi*(0:20)/20;vy = cos(t).*exp(-0.4*t);vstem(t,y,g);vhold on;vstairs(t,y,r);vhold off;vt = pi*(0:0.02:2);vx = sin(t); y=cos(t); z = cos(2*t);vplot3(x,y,z,b-,x,y,

7、z,bd);vview(-82,58), box on, legend(链,宝石);vx = -10:0.1:10;vy = -10:0.1:10;v vX,Y = meshgrid(x,y);vZ = X.2+Y.2;vmesh(Z);三维图形效果v透视v镂空v裁剪透 视vX0,Y0,Z0 = sphere(30);vmesh(X0,Y0,Z0);vshading interpvhidden offvaxis equal, axis off镂 空vt = linspace(0,2*pi,100); r = 1-exp(-t/2).*cos(4*t);vx,y,z = cylinder(r,6

8、0);vii = find(x0);vz(ii) = NaN;vsurf(x,y,z); colormap(spring); shading interp裁 剪vx = -8:0.05:8; y = x; vX,Y = meshgrid(x,y); ZZ = X.2-Y.2;vii = find(abs(X)6|abs(Y)6);vZZ(ii) = zeros(size(ii);vsurf(X,Y,ZZ), shading interp; colormap(copper)特殊图形指令v面域图 areav直方图 bar barh bar3 bar3hv饼图 pie pie3v填色图 fill f

9、ill3面域图 areavx = -2:2vy = 3,5,2,4,1;3,4,5,2,1;5,4,3,2,5vcum_sum = cumsum(y);varea(x,y,0)vlegend(要素A,要素B,要素C),grid on,colormap(spring)直方图 bar barhvx = -2:2vy = 3,5,2,4,1;3,4,5,2,1;5,4,3,2,5vsubplot(1,2,1),bar(x,y,stacked)vxlabel(x), ylabel(Sigma y), colormap(cool) vlegend(要素A,要素B,要素C)vsubplot(1,2,2),

10、 barh(x,y,grouped)vxlabel(y), ylabel(x)vlegend(要素A,要素B,要素C)直方图 bar3 bar3hvsubplot(1,2,1), bar3(x,y,1)vxlabel(要素ABC), ylabel(x),zlabel(y)vcolormap(summer)vsubplot(1,2,2), bar3h(x,y,grouped)vylabel(y), zlabel(x)饼图 pie pie3va = 1,1.6,1.2,0.8,2.1;vsubplot(1,2,1), pie(a,1 0 1 0 0),vlegend(1,2,3,4,5);vsubplot(1,2,2), pie3(a),colormap(cool)填色图 fill vn = 10;vdt = 2*pi/n; t = 0:dt:2*pi;vt = t,t(1);vx = sin(t); y = cos(t);vfill(x,y,c); axis offvgtext(十边行);填色图 fill3vxc = ones(2,4)/2;vx = xc;0 1 1 0;vy = xc;0 0 1 1;vz = 1 1 1 1;0 0 0 0;0 0 0 0;vc = 1