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1、以下为三个分布的动画演示程序，直接运行:function dandn(action)%X2分布、t分布和f分布的性质及近似计算%制作人：幸玮石岩顾秋容%All Rights Reserved% 2008.12%无输入参数时进行初始程序，否则调界面参数if n argi n1,action= i nitialize;else%看是哪种分布data=get(gco, UserData);pdflabel=data(4);%图形显示参数，调试时用switch pdflabelcase 1xstart=0;%x轴起始点width=120;%x轴范围xdis=30;%x轴刻度间距len th=0.24;
2、%y轴范围ydis=0.03;%y轴刻度间距speed=0.6;%动画演进速率case 2width=6;xdis=3;len th=0.42;ydis=0.05;speed=0.5;case 3width=2;xdis=0.5;len th=4;ydis=0.4;speed=0.8;endend%初始化模块if strcmp(action,initialize)%数据初始化%分布函数选择pdflabel=0;d=inputdlg(输入分布函数类型:,选择分布函数,1,x2 ); if strcmp(d, x2)pdflabel=1;elseif strcmp(d, t)pdflabel=2;
3、elseif strcmp(d, f)pdflabel=3;end%不符合的输入报错if pdflabel=0errordlg(分布函数只能选择 x2,t与f) returnend%整体用户界面建立，图形显示窗口嵌入figNumber=figure( .Name，Changing of the X2 destribution functionNumberTitle ,off,.Visible ,off );axes( .Units ,normalized,.Visible ,off ,.Position ,0.06 0.065 0.70 0.9);%显示初始现实画面switch pdflabe
4、lcase 1%初始显示参数xstart=0;%x轴起始点width=120;%x轴范围xdis=30;%x轴刻度间距lenth=0.24;%y轴范围ydis=0.03;%y轴刻度间距%画背景图plot(xstart xstart+width,lenth lenth,b);hold onplot(xstart xstart+width,lenth lenth,r);plot(xstart xstart+width,lenth lenth,black);legend( X2分布,正态分布);axis(xstart xstart+width 0 lenth);grid onset(gca, XTi
5、ck ,xstart:xdis:xstart+width); set(gca, YTick ,0:ydis:lenth);hold off%分布函数动画初始参数m=0;n=1;case 2width=6;xdis=3;len th=0.42;ydis=0.05;b);r-);black);plot(-width -width width,0 len th len th, hold onplot(-width -width width,0 len th len th, plot(-width -width width,0 len th len th, legend( T分布,正态分布);grid
6、 onaxis(-width width 0 len th);set(gca, XTick，-width:xdis:width); set(gca, YTick ,0:ydis:lenth);hold off m=0;n=2;otherwisewidth=2;xdis=0.5;len th=4; ydis=0.4;plot(width,0, b); hold onplot(width,0, r);legend( f分布,正态分布);axis(O width 0 lenth);grid onset(gca, XTick ,O:xdis:width);set(gca, YTick ,0:ydis:
7、lenth);hold off%f分布输入nn=inputdlg(输入 n 的值:,获取 n,1,5); n=str2double (n 1);if n=4errordlg(要使正态逼近式成立 n必须大于4!) returnendm=1;end%按钮显示位置top=0.95;left=0.80;btn Wid=0.15;btnH t=0.08;spac in g=0.02;% “ Start ”按钮btnNu mber=1;labelStr= Start;callbackStr= da ndn (start);%显示按钮btnPos=left top-btnHt btnWid btnHt;ui
8、c on trol(.Style ,pushbutton,.Units ,normalized,.Position ,btnPos, .String ,labelStr, .Callback ,callbackStr, .UserData ,btnNumber m n pdflabel);%调用时的句柄参数传递%关闭按钮yPos=top-(bt nH t+spaci ng);uic on trol(.Style ,push,.Units ,normalized,.Position ,left yPos-btnHt btnWid btnHt,.String ,Close,.Callback ,c
9、lose(gcf);set(figNumber, Visible ,on );%显示初始图像% “ Start ”按钮执行程序elseif strcmp(action,start)%参数初始化data=get(gco, UserData);method=data(1);m=data(2);n=data(3);% “ Stop ”按钮设置，点击开始后替换“Start ”按钮btnNu mber=2;labelStr= Stop;callbackStr= da ndn (stop);top=0.95;left=0.80;bt nWid=0.15;bt nH t=0.08;btnPos=left t
10、op-btnHt btnWid btnHt;stophld=uic on trol(.Style ,pushbutton,.Units，normalized,.Position ,btnPos, .String ,labelStr, .Callback ,callbackStr, .UserData ,btnNumber m n pdflabel);%画图程序switch pdflabelcase 1while (method=1)%当未点击“ Stop 则继续执行%画x2分布密度函数a=n/2;b=2;x=xstart:0.1:xstart+width;y=gampdf(x,a,b);plo
11、t(x,y, b ,EraseMode ,normal);hold on%画近似正太分布密度函数y仁n ormpdf(x, n,(2* 门)人0.5);plot(x,y1, r-);%图形参数调节axis(xstart xstart+width 0 len th);set(gca, XTick ,xstart:xdis:xstart+width);set(gca, YTick ,0:ydis:lenth);grid on ;legend( X2分布,正态分布);%显示当前ntemp=nu m2str(floor( n);str=strcat( n= ,temp);text(92,0.2,str
12、);%显示当前最大间距dis=nu m2str(max(abs(y-y1);str=strcat( dis= ,dis);text(92,0.187,str);%动画指令draw now;hold off;n=n+speed;%看stop是否按下data=get(gco, UserData);method=data(1);%更新传递参数set(stophld, Userdata ,btnNumber m n pdflabel);endcase 2while (method=1)%画t分布密度函数x=-width:0.1:width;y=tpdf(x, n);plot(x,y, EraseMod
13、e ,normal);hold on%画近似正太分布密度函数y仁n ormpdf(x,0,( n/(n-2)人0.5);plot(x,y1, r-);%图形参数调节axis(-width width 0 len th);set(gca, XTick ，-width:xdis:width);set(gca, YTick ,0:ydis:lenth);grid on ;legend( T分布,正态分布);%显示当前ntemp=nu m2str(floor( n);z=strcat( n= ,temp);text(3.3,0.335,z);%显示当前最大间距dis=nu m2str(max(abs(y-y1);str=strcat( dis= ,dis);text(3.3,0.315,str);%动画指令draw now;hold off;n=n+speed;%看s
