UC知道用matlab画高次多项式出现错误
来源：百度知道 编辑：UC知道 时间：2024/06/07 11:44:02
用一些数据拟合出一个多项式
f(x) = p1*x^3 + p2*x^2 + p3*x + p4
Coefficients (with 95% confidence bounds):
p1 = -0.0001818 (-0.0002212, -0.0001423)
p2 = 0.02556 (0.01846, 0.03267)
p3 = -1.062 (-1.486, -0.6379)
p4 = 11.92 (3.522, 20.32)
但在画出其图形时总是出现错误.
p1 =-0.0001818;
p2 =0.02556;
p3 =-1.062;
p4 =11.92;
f= p1*x^3 + p2*x^2 + p3*x + p4;
x=50:70;
plot（x,f）
运行总是出现Error using ==> mpower
Matrix must be square.
求达人帮忙解决。。。
f(x) = p1*x^3 + p2*x^2 + p3*x + p4
Coefficients (with 95% confidence bounds):
p1 = -0.0001818 (-0.0002212, -0.0001423)
p2 = 0.02556 (0.01846, 0.03267)
p3 = -1.062 (-1.486, -0.6379)
p4 = 11.92 (3.522, 20.32)
但在画出其图形时总是出现错误.
p1 =-0.0001818;
p2 =0.02556;
p3 =-1.062;
p4 =11.92;
f= p1*x^3 + p2*x^2 + p3*x + p4;
x=50:70;
plot（x,f）
运行总是出现Error using ==> mpower
Matrix must be square.
求达人帮忙解决。。。
p1 =-0.0001818;
p2 =0.02556;
p3 =-1.062;
p4 =11.92;
f= p1.*x.^3 + p2.*x.^2 + p3.*x + p4;
%应该用点运算（.x和.^）
x=50:70;
plot(x,f)% 此处也已修改
%我已试过了，没错了。