hw11_p04 - for i = 1:n sum_x = sum_x + x(i); sum_y = sum_y...

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% To get a first derivatives at each point, % i = 1 --> Second order finite difference % i = 2 ~ n-1 --> Second order central difference % i = n --> Second order backward difference t = [0, 5, 10, 15, 20, 25]; % Time (s) T = [80 44.5 30.0 24.1 21.7 20.7]; % Position (m) n = length(t); h = 5.0; Ta = 20.0; T % Numerical differentiation with finite differences % velocity for i = 1:n if i == 1 T_prime(i) = (-3.0*T(i) + 4.0*T(i+1) - T(i+2))/(2.0*h); elseif i == n T_prime(i) = (3.0*T(i) - 4.0*T(i-1) + T(i-2))/(2.0*h); else T_prime(i) = (T(i+1) - T(i-1))/(2.0*h); end end e % Linear regression: y = a0 + a1*x x = T - Ta; y = T_prime; y sum_x = 0.0; sum_y = 0.0; sum_xy = 0.0; sum_x2 = 0.0; x_m = 0.0; y_m = 0.0;
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Unformatted text preview: for i = 1:n sum_x = sum_x + x(i); sum_y = sum_y + y(i); sum_xy = sum_xy + x(i)*y(i); sum_x2 = sum_x2 + x(i)*x(i); end x_m = sum_x/n; y_m = sum_y/n; y a1 = (n*sum_xy - sum_x*sum_y)/(n*sum_x2 - sum_x*sum_x); a0 = y_m - a1*x_m; a k = -a1; y_regressed = a0 + a1*x; plot (x, y, 'o', x, y_regressed); xlabel('T-Ta'); ylabel('dT/dt'); legend('Data', 'Regression'); l % open file fid4 = fopen('hw11_p04_answer.txt','a'); % 'wt' means "write text" if (fid4 < 0) error('could not open file "hw11_p04_answer.txt"'); end; e fprintf(fid4, '\na1 = %10.5f with an intercept %10.5f\n', a1, a0); fprintf(fid4, 'k = %10.5f with an intercept\n', k); fclose(fid4);...
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hw11_p04 - for i = 1:n sum_x = sum_x + x(i); sum_y = sum_y...

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