作业帮matlab 作拟合的直线例如x,y如下x=[12.10 11.96 11.80 11.65 11.50];y=[23.00 34.00 45.00 56.00 67.00];并求直线的斜率能不能说得再清楚些
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![matlab 作拟合的直线例如x,y如下x=[12.10 11.96 11.80 11.65 11.50];y=[23.00 34.00 45.00 56.00 67.00];并求直线的斜率能不能说得再清楚些](/uploads/image/z/10190806-70-6.jpg?t=matlab+%E4%BD%9C%E6%8B%9F%E5%90%88%E7%9A%84%E7%9B%B4%E7%BA%BF%E4%BE%8B%E5%A6%82x%2Cy%E5%A6%82%E4%B8%8Bx%3D%5B12.10+11.96+11.80+11.65+11.50%5D%3By%3D%5B23.00+34.00+45.00+56.00+67.00%5D%3B%E5%B9%B6%E6%B1%82%E7%9B%B4%E7%BA%BF%E7%9A%84%E6%96%9C%E7%8E%87%E8%83%BD%E4%B8%8D%E8%83%BD%E8%AF%B4%E5%BE%97%E5%86%8D%E6%B8%85%E6%A5%9A%E4%BA%9B)
matlab 作拟合的直线例如x,y如下x=[12.10 11.96 11.80 11.65 11.50];y=[23.00 34.00 45.00 56.00 67.00];并求直线的斜率能不能说得再清楚些
matlab 作拟合的直线
例如x,y如下
x=[12.10 11.96 11.80 11.65 11.50];
y=[23.00 34.00 45.00 56.00 67.00];
并求直线的斜率
能不能说得再清楚些
matlab 作拟合的直线例如x,y如下x=[12.10 11.96 11.80 11.65 11.50];y=[23.00 34.00 45.00 56.00 67.00];并求直线的斜率能不能说得再清楚些
>> help polyfit
POLYFIT Fit polynomial to data.
POLYFIT(X,Y,N) finds the coefficients of a polynomial P(X) of
degree N that fits the data,P(X(I))~=Y(I),in a least-squares sense.
[P,S] = POLYFIT(X,Y,N) returns the polynomial coefficients P and a
structure S for use with POLYVAL to obtain error estimates on
predictions.If the errors in the data,Y,are independent normal
with constant variance,POLYVAL will produce error bounds which
contain at least 50% of the predictions.
The structure S contains the Cholesky factor of the Vandermonde
matrix (R),the degrees of freedom (df),and the norm of the
residuals (normr) as fields.
[P,S,MU] = POLYFIT(X,Y,N) finds the coefficients of a polynomial
in XHAT = (X-MU(1))/MU(2) where MU(1) = mean(X) and MU(2) = std(X).
This centering and scaling transformation improves the numerical
properties of both the polynomial and the fitting algorithm.
Warning messages result if N is >= length(X),if X has repeated,or
nearly repeated,points,or if X might need centering and scaling.
See also POLY,POLYVAL,ROOTS.
方程式y=ax+b，记得把x和y写成列向量
clc
A = [x ones(size(x)]
ab = inv(A'*A)*A'*y
a=ab(1)
b=ab(2)