initial commit / add all books

2 files changed, 23 insertions, 0 deletions

diff --git a/27/CH8/EX8.3.1/8_3_1.jpg b/27/CH8/EX8.3.1/8_3_1.jpg
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diff --git a/27/CH8/EX8.3.1/Example_8_3_1.sce b/27/CH8/EX8.3.1/Example_8_3_1.sce
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+a=10;

+b=3;

+  function xd=linear831(t,x)

+    xd(1)=a-x(1)-((4*x(1)*x(2))/(1+x(1)^2));

+    xd(2)=(b*x(1))*(1-(x(2)/(1+x(1)^2)));

+             //x(dot);   x(2) means y.

+             //y(dot);   x(1) means x.; 

+  endfunction

+  bound=[0,3,3,7];        //Bounds of x-axis and y-axis as [xmin ymin xmax ymax], change them according to your needs.

+  nrect=25;     //increase it to get more number of curves, i.e. more information will be available.

+  set(gca(),"auto_clear","off")        //hold on

+  x=linspace(bound(1),bound(3),nrect);

+  y=linspace(bound(2),bound(4),nrect);

+  x0=[];

+ 

+ for i=1:25

+     x0=[x(i);y(i)];

+     t0=0;

+     t=0:0.01:3000;

+     xout=ode(x0,t0,t,linear831);

+     plot2d(xout(1,:),xout(2,:));

+ end

+  xtitle('Phase Portrait','x-axis ( x )','y-axis ( y )')
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