三次样条插值法
三次样条插值法
h0=figure('toolbar','none',...
'position',[200 50 350 450],...
'name','实例86');
h1=axes('parent',h0,...
'position',[0.10 0.45 0.8 0.5],...
'visible','off');
x=0:0.2:2*pi;
y=sin(x);
plot(x,y)
b1=uicontrol('parent',h0,...
'units','points',...
'tag','b1',...
'style','pushbutton',...
'string','三次样条插值',...
'backgroundcolor',[0.75 0.75 0.75],...
'position',[20 60 70 20],...
'callback',[...
'y=0,',...
'sy=0,',...
'strn1=get(e2,''string'');,',...
'n1=str2num(strn1);,',...
'strn2=get(e3,''string'');,',...
'n2=str2num(strn2);,',...
'x=n1:0.2:n2;,',...
'i=1;,',...
'for t=n1:0.2:n2,',...
'y(i)=sin(t);,',...
'sy(i)=san(t,n1,n2);,',...
'i=i+1;,',...
'end,',...
'plot(x,y,''b*'',x,sy,''r-''),',...
'axis([0 7 -1.5 1.5]),',...
'legend(''sin(x)'',''N-Hermite插值'')']);
b2=uicontrol('parent',h0,...
'units','points',...
'tag','b2',...
'style','pushbutton',...
'string','误差比较',...
'backgroundcolor',[0.75 0.75 0.75],...
'position',[170 60 70 20],...
'callback',[...
'strdn1=get(e2,''string'');,',...
'n1=str2num(strdn1);,',...
'strdn2=get(e3,''string'');,',...
'n2=str2num(strdn2);,',...
'strdn=get(e1,''string'');,',...
'dn=str2num(strdn);,',...
'dd=abs(sin(dn)-san(dn,n1,n2));,',...
'msgbox([''误差为：'',num2str(dd)],''计算结果'')']); e1=uicontrol('parent',h0,...
'units','points',...
'tag','e1',...
'style','edit',...
'fontsize',12,...
'string','1.20',...
'horizontalalignment','right',...
'backgroundcolor',[1 1 1],...
'position',[200 100 40 20]);
t1=uicontrol('parent',h0,...
'units','points',...
'tag','t1',...
'style','text',...
'string','误差点：',...
'fontsize',12,...
'backgroundcolor',[0.75 0.75 0.75],...
'position',[160 100 40 20]);
e2=uicontrol('parent',h0,...
'units','points',...
'tag','e2',...
'style','edit',...
'fontsize',12,...
'string','1.00',...
'horizontalalignment','right',...
'backgroundcolor',[1 1 1],...
'position',[20 85 40 20]);
t2=uicontrol('parent',h0,...
'units','points',...
'tag','t2',...
'style','text',...
'string','第一节点：',...
'fontsize',12,...
'backgroundcolor',[0.75 0.75 0.75],...
'position',[15 105 50 20]);
e3=uicontrol('parent',h0,...
'units','points',...
'tag','e3',...
'style','edit',...
'fontsize',12,...
'string','3.00',...
'horizontalalignment','right',... 'backgroundcolor',[1 1 1],... 'position',[100 85 40 20]); t3=uicontrol('parent',h0,...
'units','points',...
'tag','t3',...
'style','text',...
'string','第二节点：',...
'fontsize',12,...
'backgroundcolor',[0.75 0.75 0.75],... 'position',[95 105 50 20]); b3=uicontrol('parent',h0,...
'units','points',...
'tag','b3',...
'style','pushbutton',...
'string','关闭',...
'backgroundcolor',[0.75 0.75 0.75],... 'position',[100 20 60 20],... 'callback','close');