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graphy_plot(A,xy,1,0.5), % gplot(A,xy) 】 1.3.4 参考程序
graphy_plot.m
【 function y=graphy_plot(A,xy,l,p) %画矩阵的有向结构图。 A为邻接矩阵，xy为顶点坐标，l控制参数，l=0，画无向图；
%l~=0,画有向图。p为控制箭头大小的参数。 a=-max(abs(xy(:,1)))*1.1;b=max(abs(xy(:,1)))*1.1; c=-max(abs(xy(:,2)))*1.1;d=max(abs(xy(:,2)))*1.1; if l=0
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数学实验与Matlab
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gplot(A,xy),axis([a b c d]),hold on, elseif l~=0
U=[];V=[];X=[];Y=[]; n=length(A(:,1)) ; for i=1:n
k=find(A(i,:)~=0); m=length(k); if(m~=0) for j=1:m
u(1)=(xy(k(j),1)-xy(i,1)); v(1)=(xy(k(j),2)-xy(i,2));
u(2)=eps; v(2)=eps; U=[u;U];V=[v;V];
X=[[xy(i,1) xy(k(j),1)];X]; Y=[[xy(i,2) xy(k(j),2)];Y]; end
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数学实验与Matlab
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text(xy(i,1),xy(i,2),['\\bullet\\leftarrow\\fontsize{16}\\it{V}',? um2str(i)]); hold on, end end
gplot(A,xy),axis([a b c d]),hold on,
h=quiver(X,Y,U,V,p);set(h,'color','red');hold on,
plot(xy(:,1),xy(:,2),'k.','markersize',12),hold on,
end , hold off 】
实验２．函数的可视化与Matlab作 2.1 实验与观察：函数的可视化
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数学实验与Matlab
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2.1.1 Matlab二维绘图命令 1.周期函数与线性p－周期函数 ◆ 观察 ：
【 clf, x=linspace(0,8*pi,100); F=inline('sin(x+cos(x+sin(x)))'); y1=sin(x+cos(x+sin(x)));
y2=0.2*x+sin(x+cos(x+sin(x))); plot(x,y1,'k:',x,y2,'k-')
legend('sin(x+cos(x+sin(x))','0.2x+sin(x+cos(x+sin(x)))',2) 】
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数学实验与Matlab
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2. plot指令：绘制直角坐标的二维曲线
3. 图形的属性设置和屏幕控制
【 h=plot([0:0.1:2*pi],sin([0:0.1:2*pi])); grid on
set(h,'LineWidth',5,'color','red'); set(gca,'GridLineStyle','-','fontsize',16) 】
◆设置y坐标的刻度并加以说明，并改变字体的大小。
【 h=plot([0:0.1:2*pi],sin([0:0.1:2*pi]));grid on，
set(gca,'ytick',[-1 -0.5 0 0.5 1]), set(gca,'yticklabel','a|b|c|d|e'),
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