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matlab用最小二乘法求一形如Y=ct^m(c和m为待定系数)的多项式,使之与下列数据相拟合,

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matlab用最小二乘法求一形如Y=ct^m(c和m为待定系数)的多项式,使之与下列数据相拟合,
数据如下(19,19.0)(25,32.3)(31,49.0)(38,73.3)(44,97.8)
matlab用最小二乘法求一形如Y=ct^m(c和m为待定系数)的多项式,使之与下列数据相拟合,
程序:
clear;
clc;
t = [19 25 31 38 44];
y = [19 32.3 49 73.8 97.8];
y = y';
t = t';
st_ = [0.5 0.5]; %%%% 起始点
ft_ = fittype('c*t^m' ,...%%%% 公式
'dependent',{'y'},'independent',{'t'},...%%% 变量和自变量
'coefficients',{'c','m'}); %%% 系数
[cf,good]= fit(t,y,ft_ ,'Startpoint',st_)
h_ = plot(cf,'fit',0.95);
legend off; % turn off legend from plot method call
set(h_(1),'Color',[1 0 0],...
'LineStyle','-','LineWidth',2,...
'Marker','none','MarkerSize',6);
hold on,plot(t,y,'*')
结果;
cf =
General model:
cf(t) = c*t^m
Coefficients (with 95% confidence bounds):
c = 0.0588 (0.05147,0.06612)
m = 1.96 (1.926,1.994)
good =
sse:0.2267
rsquare:0.9999
dfe:3
adjrsquare:0.9999
rmse:0.2749
贴图:
这个就算了,避免被拉去审,效果很好,可以自己运行一下看看