1 files changed, 18 insertions, 0 deletions
diff --git a/1673/CH3/EX3.19/3_19.sce b/1673/CH3/EX3.19/3_19.sce
new file mode 100755
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+//error in lagrenge's interpolation
+//example 3.19
+//page 107
+clc;clear;close;
+x=[0 %pi/4 %pi/2];
+y=[0 0.70711 1.0];
+deff('y=l0(x)','y=((x-0)*(x-%pi/2))/((%pi/4)*(-%pi/4))')
+x=poly(0,'x');
+disp(l0(x),'l0(x)=');
+deff('y=l1(x)','y=((x-0)*(x-%pi/4))/((%pi/2)*(%pi/4))')
+x=poly(0,'x');
+disp(l1(x),'l1(x)=');
+f_x=l0(%pi/6)*y(2)+l1(%pi/6)*y(3);
+err=abs(f_x-sin(%pi/6));
+deff('y=f(x)','y=((x-0)*(x-%pi/4)*(x-%pi/2))/6');
+if abs(f(%pi/6))>err then
+    printf('\n\n the error agrees with the actual error')
+end
+\ No newline at end of file