Licensed Electrical & Mechanical Engineer
BMayer@ChabotCollege.edu
Engineering-25: Computational Methods
1
Bruce Mayer, PE
ENGR-25_Linear_Regression_Tutorial.ppt

% Bruce Mayer, PE * 23Aug06
% ENGR25 * Problem 4-32, Part (a)
% file = Prob4_32a_2D_Termperature_Field.m
%
% Summation is on n-ODD; make index vector over 1...19
n = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19];
%
% calc the magnitude each term of w(x,y) separately wTerm = abs((2./n).*sin(n*pi/2).*(sinh(n*pi/2)./sinh(n*pi)));
%
% scale all terms relative to the first term where n = 1
% display as COL-vector my using transpose operator (')
% use Sci-Notation format format short e disp( 'The Relative Magnitude of the First 10 terms of w(x,y):' ) disp(wTerm'/wTerm(1))
Engineering-25: Computational Methods
2
Bruce Mayer, PE
ENGR-25_Linear_Regression_Tutorial.ppt

% Bruce Mayer, PE * 23Aug06
% ENGR25 * Problem 4-32, Part (b)
% file = Prob4_32b_2D_Termperature_Field.m
%
% Set Constants
T_1 = 70;T_2 = 200;
W = 2;L = 2; x = L/2;y = W/2;
%
% Intialize the Sum, and Error, and counter
Sum = 0
Chg = 10 n = 1 % index m = 0 % Term counter
%
% The Loop while abs(Chg) > .01 % 0.01 = 1%
Sum_next = Sum +
(2/n)*sin(n*pi*x/L)*(sinh(n*pi*y/L)/sinh(n*pi*W/L)); if n > 1 m
Chg = ((abs(Sum_next)- abs(Sum))/abs(Sum));
ChgPct = abs(Chg*100) end
Sum = Sum_next n = n + 2; % only ODD indices m = m + 1; % count the number to terms end
%
% Calc w11 using last sucessful Sum w11 = (2/pi)*Sum;
%
% calc Tmid
Tmid = (T_2- T_1)*w11 + T_1;
%
%display results disp( 'The temperature in the middle of the plate is:' ) disp(Tmid) disp( 'The number of series terms required is:' ) disp(m)
Engineering-25: Computational Methods
3
Bruce Mayer, PE
ENGR-25_Linear_Regression_Tutorial.ppt