MATLAB數(shù)據(jù)擬合例子(共3頁(yè))

1、MATLAB數(shù)據(jù)擬合例子（一次函數(shù)、指數(shù)函數(shù)、雙曲線）(2010-06-03 01:44:30)標(biāo)簽：分類：一次函數(shù)： （a+bx = y） %先求出擬合函數(shù)format long;x = 2001 2002 2003 2004 2005 2006 2007 2008 2009;y = 32.2 31.3 29.7 28.6 27.5 26.1 25.3 23.7 22.7;d = 1 1 1 1 1 1 1 1 1; a=d;x;b = a*y;a=a*a;c=abc = 1.0e+003 * 2.436797222221444 -0.001201666666666%所以，擬合函數(shù)為 y =

2、 1.0e+003 *(2.436797222221444 - 0.001201666666666*x%根據(jù)擬合函數(shù)求估測(cè)值format short;x = 2010, 2011, 2012, 2013, 2014 1.0e+003 *(2.436797222221444 - 0.001201666666666*x)ans = 21.4472 20.2456 19.0439 17.8422 16.6406 指數(shù)函數(shù)：( y = exp(a + b*x)） x = 2001 2002 2003 2004 2005 2006 2007 2008 2009;y = 21.5 15.9 11.8 8.

3、7 6.5 4.8 3.5 2.6 2.0;y=log(y);d = 1 1 1 1 1 1 1 1 1; a=d;x;b = a*y;a=a*a;c=ab c = 601.9448 -0.2993 %所以，擬合函數(shù)為 y = exp(601.9448 - 0.2993*x) %根據(jù)擬合函數(shù)求估測(cè)值 x = 2010, 2011, 2012, 2013, 2014 exp(601.9448 - 0.2993*x)ans =1.4216 1.0539 0.7813 0.5792 0.4294 雙曲線： （1/y = a + b/x）format long;x = 2002 2003 2004 2005 2006 2007 2008 2009;y = 46.2 32.6 26.7 23.0 20.0 18.9 17.5 16.3;t=1./x;u = 1./y;d = 1 1 1 1 1 1 1 1;a = d; t;b = a*u;a=a*a;c=ab c = 1.0e+004 * 0.001110403638151 -2.218020870743078 format short;x = 2010, 2011, 2012, 2013, 2014 x./(1.0e+004 * (0.001110403638151*x -2.