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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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+++ b/27/CH8/EX8.3.1/Example_8_3_1.sce
@@ -0,0 +1,23 @@
+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 )')
+\ No newline at end of file