How can I make a table bisection method and put all iterables step by step?

a = input('a = ');
b = input('b = ');
E = input('Error = ');
N = log((b-a)/E)/(log(2))
f = @(x) x^2 - 3;

format long
for i = 1:N
    c =(a+b)/2;
    T = table(N,a,b,c,f(c));
    T(N:5,:)
    disp(T);
    if f(c) * f(a) > 0
        a = c;
    else 
        b = c;
    end
%     if (abs(b-a) / 2^N) <= E || f(c) == 0
        
%         break
%     end
end
final_ans = c;
fprintf('root is %f\n',final_ans);

% OUTPUT
            %N               a        b         c             Var5     
    %________________    _______    ____    ________    ______________

    %7.64385618977472    1.71875    1.75    1.734375    0.008056640625

%root is 1.734375

Answer 1

[Jan]

With your current method the table is overwritten in each iteration. Create the table before the loop and insert the new values only.

[EDITED] Some code:

a = 1;
b = 2;
E = 1e-6;
N = ceil(log((b - a) / E) / log(2));  % CEIL() !
f = @(x) x^2 - 3;

T = table('Size', [N, 5], ...
    'VariableTypes', {'double', 'double', 'double', 'double', 'double'}, ...
    'VariableNames', {'N', 'a', 'b', 'c', 'fc'});
for i = 1:N
    c = (a + b) / 2;
    T(i, :) = {i, a, b, c, f(c)};  % Fill in data in existing table
    if f(c) * f(a) > 0
        a = c;
    else 
        b = c;
    end
end
disp(T)

[Mahdi Ayyad]

But this is the output

% OUTPUT

%N a b c Var5

%________________ _______ ____ ________ ______________

%7.64385618977472 1.71875 1.75 1.734375 0.008056640625

%root is 1.734375

it's not overwritten, but i tried to put the table before the loop and still the same.

[Jan]

"i tried to put the table before the loop" - Then please post the corresponding code. This is more efficient for solving your problem than letting the readers guess, what you have done exactly.

I still do not like the table syntax and avoid using this type in productive code. But see [EDITED] in my answer for an explicit example.