MATLAB: I cannot get this to work…I keep getting errors all over the place. Could someone kindly explain

false-position

function Burke_FP()
clear
clc
t1 = input('Please input your upper bounds')
f1 = myfunc(t1);
t2 = input('Please input your lower bounds')
f2 = myfunc(t2);
t = linspace (t1,t2,100);
error = 10;
f = myfunc(t);
plot(t,f)
while error > 1e-4
     tr = t2 - f2*(t1 - t2)/(f1-f2);
      fr = myfunc(tr);
      if sign(fr) == f1
          t1 = tr;
          f1 = fr;
      else
          t2 = tr;
          f2 = fr;
      end
      %recompute error
      error = abs(fr);
  end
  tr   
  end
function out = myfunc(in)
in.^2-5
end

Best Answer

You have
if sign(fr) == f1
but sign(fr) is going to be -1 (exactly), 0 (exactly), or +1 (exactly), none of which are likely to be exactly equal to fl.
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