diff1c3.m

Micro Electronic Device Fundermental

format short
%syms x
%plot(x,y1),grid
%plot(x,y1,x,g1),grid
%h=((48*0.5e-4)/135)^(1/4)
h=0.02
x=1:h:1.12
y1=exp(-x.^2).*cos(20*x)
g1=-2*x.*exp(-x.^2).*cos(20*x)-20*exp(-x.^2).*sin(20*x)
m1=(1/(2*h))*(exp(-(x+h).^2).*cos(20*(x+h))-exp(-(x-h).^2).*cos(20*(x-h)))
det2=abs(g1-m1)
j=length(x);
fprintf('------------------------------------------------------------\n')
fprintf('  x               g1               m1                det1\n');
fprintf('------------------------------------------------------------\n')
for ii=1:j,
    fprintf('%-10.4f       %-10.4f      %-10.4f      %-10.4e\n',x(ii),g1(ii),m1(ii),det2(ii));
end
plot(x,y1),grid