ln2.m

Matlab做的数值计算实验

%利用三种不同方法计算Ln2，输出结果
clear %清除变量
clc %清屏
fprintf('three methods to caculate Ln(2)\n');
fprintf('method1 \n');
i = 1;
delta = 5.0e-6;
Snew = 1; Sold = 0;
fprintf('        n       method1(n)\n');    
while abs(Snew - Sold) > delta
  fprintf('%10.3g     %15.10g\n', i, method1(i));
   Sold = Snew;
   i = i + 1;
   if i > 500
       break;
   end
   Snew = method1(i);
end
fprintf('%10.3g     %15.10g\n', i, method1(i));

fprintf('          n       method2(n)\n');   
i = 3;
Sold = 0; Snew = method2(1);
while abs(Snew - Sold) > delta
    fprintf('%10.3g     %15.10g\n', i, method2(i));
    Sold = Snew;
    i = i + 1;
    Snew = method2(i);
end
fprintf('%10.3g     %15.10g\n', i, method2(i));

fprintf('        n       method3(n)\n');  
i = 1;
Sold = 0; Snew = 0.5;
while abs(Snew - Sold) > delta
    fprintf('%10.3g     %15.10g\n', i, method3(i));
    Sold = Snew;
    i = i + 1;
    Snew = method3(i);
end
fprintf('%10.3g     %15.10g\n', i, method3(i));