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Example 1: 07-hBzPR/plotCensus.mload census.mat plot(cdate, pop, 'o'); xlabel('~'); ylabel('Hf]GʸU^');

Ywb褸 2002 ~`HfAi polyfit ӧX@hHGwIC]hƬ 3AhiJpUG

Example 2: 07-hBzPR/polyfit01.mwarning off % RCNiĵiT load census.mat plot(cdate, pop, 'o'); p3 = polyfit(cdate, pop, 3); cdate2 = 1790:2002; pop2 = polyval(p3, cdate2); plot(cdate, pop, 'o', cdate2, pop2, '-'); xlabel('~'); ylabel('Hf]GʸU^'); legend('ڤHf', 'wHf'); popAt2002 = polyval(p3, 2002)popAt2002 = 282.5332

Ѧuwib 2002 ~Hf 282.5 ʸUHC

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Example 3: 07-hBzPR/polyfit02.mwarning off % RCNiĵiT load census.mat cdate2 = min(cdate):(max(cdate)+30); curve = zeros(7, length(cdate2)); for i = 1:7 curve(i,:) = polyval(polyfit(cdate,pop,i), cdate2); end plot(cdate, pop,'o', cdate2, curve); legend('ڸ', 'order=1', 'order=2','order=3', 'order=4', 'order=5', 'order=6', 'order=7'); xlabel('~'); ylabel('Hf]GʸU^');

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Hint
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