The least squares quadratic function is given as Code a Matlab program

The following data are given as the results of an experiment. The least squares quadratic function is given as Code a Matlab program that calculates the total squared error (E).

x = [5.435   4.635   3.835   3.035   2.325   1.435   0.635]
y = [1.00     1.28     1.70     2.20     2.97     4.35     7.50  ]

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

[Walter Roberson]

The question appears to be incomplete. It appears to be a copy and paste of an assignment but with a formula skipped.

[Rena Berman]

(Answers Dev) Restored Question.

Answer 1

[Star Strider]

I’m not certain what you want to do.

Here is one possibility:

x = [5.435   4.635   3.835   3.035   2.325   1.435   0.635];
y = [1.00     1.28     1.70     2.20     2.97     4.35     7.50  ];

p = polyfit(x, y, 2);                                               % Quadratic Function Fit
v = polyval(p, x);                                                  % Evaluate
TSE = sum((v - y).^2);                                              % Total Squared Error

figure(1)
plot(x, y, 'bp')
hold on
plot(x, v, '-r')
hold off
grid

[Star Strider]

My pleasure.

If my Answer solved your problem, please Accept it.

[Star Strider]

With respect to your re-titled Question: ‘what is different between while and for in matlab’:

A for loop sets a specific number of iterations at the outset:

for k1 = 1:10
    ... CODE ...
end

will run the code in the loop 10 times.

A while loop runs until a specific condition within the loop is met:

while q < 10
    q = ...;
end

will run as many iterations as necessary until, in this example, ‘q’ is greater than or equal to 10, then the loop stops.