1 files changed, 56 insertions, 0 deletions
diff --git a/260/CH13/EX13.17/13_17.sce b/260/CH13/EX13.17/13_17.sce
new file mode 100644
index 000000000..45424b296
--- /dev/null
+++ b/260/CH13/EX13.17/13_17.sce
@@ -0,0 +1,56 @@
+//Eg-13.17
+//pg-563
+
+clear
+clc
+
+deff('out = func(in1,in2)','out = in1^3*(cos(in2))^2 - in1*sin(2*in2)')
+// Using the analytical expression in the question
+deff('out = F(in1)','out = atan(0.5*(in1^2 + exp(-in1^2) - 1))')
+
+
+x(1) = 0;
+y(1) = 0;
+
+h = 0.1;
+
+for(i = 1:10)
+    x(i+1) = x(i) + h;
+    
+end
+
+//Using RK method
+
+a = (2^0.5-1)/2;
+b = (2-2^0.5)/2;
+c = -(2^0.5)/2;
+d = 1 + (2^0.5)/2;
+
+printf('   t          y         F(x,y)\n')
+
+for(i = 1:4)
+    
+    k1(i) = h*func(x(i),y(i));
+    k2(i) = h*func(x(i)+h/2,y(i)+k1(i)/2);
+    k3(i) = h*func(x(i)+h/2,y(i)+a*k1(i)+b*k2(i));
+    k4(i) = h*func(x(i)+h,y(i)+c*k2(i)+d*k3(i));
+    y(i+1) = y(i) + 1/6*(k1(i)+2*b*k2(i)+2*d*k3(i)+k4(i));
+    printf('%f    %f    %f\n',x(i),y(i),func(x(i),y(i)))
+    
+end
+
+printf('\n\nUsing Adams Predictor-Corrector Method & its comparision with the analytical solution:\n\n')
+
+h = 0.1;
+for(i = 4:6)
+    
+    yb(i+1) = y(i) + h/24*(55*func(x(i),y(i)) - 59*func(x(i-1),y(i-1)) + 37*func(x(i-2),y(i-2)) - 9*func(x(i-3),y(i-3)));
+    y(i+1) = y(i) + h/24*(9*func(x(i+1),yb(i+1)) + 19*func(x(i),y(i)) - 5*func(x(i-1),y(i-1)) + func(x(i-2),y(i-2)));
+    
+end
+
+printf('   t         yadams    yanalytical\n')
+
+for(i = 5:6)
+    printf('%f    %f    %f\n',x(i),y(i),F(x(i)))
+end