% In class 6-Mar-08 clear, clc, home fprintf('The date and time: %s \n', datestr(now))
The date and time: 10-Apr-2008 08:53:07
% Curve fitting data. % % Reading Ch. 9 % Introduction: pg 455 to 456. % 9.1.5 on page 468 % % xfit = [2:0.01:20], called x-grid. % yfit = c_1*exp(c_2*x) % % residuals: y distance between actual data and curve approximation. % % polyfit(x,y,n) % where n is the degree of the polynomial % % z = polyfit(x,y,n) % p = a_(n)*x^n + a_(n-1)*x^(n-1) + .... a_(0)*x^0. % z(1) = a_(n) % z(2) = a_(n-1) % z(n) = a_(0) % % See homework problem 8 on page 512. % % 2x^5 + 3x^3 + 1 % polyfit gives: 2x^5 + 0.335E-9x^4 + 3x^3 + 5.3E-12x + 1 % If some of the coefficients are almost zero then they basically arn't % needed. % % expect us to do: % Loops i.e. if ... else and for ... end % % % Test 2 on week 8 % must have WebCT and saclink account % 1. for loops % 2. conditional statements % if - else ... else - end % switch (controller) case{..} case{..} otherwise - end % 3. Solve systems of equations (Gauss) % 4. Read/write data files % 5. extract matrix from systems of equations and vice-versa % 6. Use Graphical method to solve a 3x3 system (Graph) % 7. Curve-fitting % a) straight line % b) exponential % c) Power function % d) polyfit/polyval % 8. User-defined functions % a) include heading 1 line % 9. Interpolation % 10. Relative error % a) absolute error: (true value) - (calculated value) % b) relative error: (absolute error)/(true value)*100 % % Note: should use moduals to do each of these things. Open book open % note. %