1、使用webread将美国年平均气温读入一个结构数组。api = 'http://climatedataapi.worldbank.org/climateweb/rest/v1/';url = [api 'country/cru/tas/year/USA'];S = webread(url)
2、S(1)
3、S(112)
4、绘制出每年的平均气温。将温度和年份转换为数字数组。将年份转换为日期时间对象以便于绘制，并将温度转换为华氏度。
5、temps = [S.data];temp衡痕贤伎s = 9/5 * temps + 32;years = [S.year];yearstoplot = datetime(years,1,1);figure plot(yearstoplot, temps);title('USA Average Temperature 1901-2012')xlabel('Year')ylabel('Temperature (^{\circ}F)')xmin = datetime(1899,1,1);xmax = datetime(2014,1,1);xlim([xmin xmax])
6、一刳噪受刃条直线与温度的最小二乘拟合过度。p = polyfit(years,temps,1);ptemps = polyval(p,years);deltat = p(1);hold onfl = plot(yearstoplot, ptemps);xlim([xmin xmax])title('USA Average Temperature Trend 1901-2012')xlabel('Year')ylabel('Temperature (^{\circ}F)')deltat = num2str(10.0*deltat);legend(fl,['Least Squares Fit, ', deltat, '^{\circ}F/decade'])hold off
