﻿ Need help in MATLAB

### Author Topic: Need help in MATLAB  (Read 526 times)

#### OfficerKenny

Ok so I have to do this problem for a class

I am confused because aren't you supposed to know the tolerance before you are able to do the iterations?  If you are able to calculate tolerance how does one do so?

#### Conan

a) is telling you to do 3 iterations
b) is telling you to figure out how many iterations it takes to reach a value with the tolerance of 10^-5, given the starting bracket.
i presume tolerance here means the distance of the current value from the minima.

#### OfficerKenny

a) is telling you to do 3 iterations
b) is telling you to figure out how many iterations it takes to reach a value with the tolerance of 10^-5, given the starting bracket.
i presume tolerance here means the distance of the current value from the minima.
Yeah I was confused by what tolerance meant as well, I assume that tolerance is the number of digits the midpoint has.  Like in this script here(This is from a different problem):
Code: [Select]
`clear all;xL = 0;xR = 1.5;f = @(x) (sin(x) - cos(3*x));alpha = 10^-6;maxloops = 25;for i = 1:maxloopsxM = (xL+xR)/2; %xM = x*if f(xM)*f(xR)<0 xL=xM;elseif f(xM)*f(xL)<0 xR=xM;endif abs(f(xM))<alpha breakendendxM;a = xM;disp("The value of x* is");disp(a);disp("The value of f(x*) is");disp(f(xM));disp("The number of iterations attempted was");disp(maxloops);disp("The maximum number of iterations performed was")disp(i);disp("A grpah of the funtion with xL=0 to xR=1.5 is now beingdisplayed");Problem3Plot;`
I set it so that the script stops once it reaches a specific alpha value, the tolerance I think is the same thing as whats happening with alpha.  At least I hope so because I already submitted the assignment.