stmak.m

演示matlab曲线拟和与插直的基本方法

% STMAK   st-宆偺娭悢偺慻棫偰
%
% ST = STMAK(CENTERS, COEFS) 偼丄偮偓偺娭悢偺st-宆傪 ST 偵奿擺偟傑偡丅
%
%         x |--> sum_j COEFS(:,j)*psi(x - CENTERS(:,j))
% 偙偙偱 psi 偼丄
%          psi(x) := |x|^2 log(|x|^2) 
%
% 偱偁傝丄|x| 偼丄儀僋僩儖 x 偺儐乕僋儕僢僪偺挿偝偱偡丅
% CENTERS 偲 COEFS 偼丄摨偠楍悢傪傕偮峴楍偱側偗傟偽側傝傑偣傫丅
%
% ST = STMAK(CENTERS, COEFS, TYPE) 偼丄偮偓偺娭悢偺st-宆傪 ST 偵奿擺
% 偟傑偡丅
%
%         x |--> sum_j COEFS(:,j)*psi_j(x)
%
% 偙偙偱丄psi_j 偼丄暥帤楍 TYPE 偵帵偝傟傞傛偆偵丄'tp00', 'tp10', 'tp01'偺
% 偄偢傟偐偱偡丅'tp' 偑僨僼僅儖僩偱偡丅
% 偙傟傜偺條乆側僞僀僾偵偮偄偰偺埲壓偺婰弎偵偍偄偰丄c_j 偼丄CENTERS(:,j) 
% 偱丄n 偼丄崁偺悢丄偡側傢偪丄size(COEFS,2) 偵摍偟偔側傝傑偡丅
%
% 'tp00': 2曄悢thin-plate僗僾儔僀儞
% psi_j(x) := phi(|x - c_j|^2), j=1:n-3, 偙偙偱丄phi(t) := t log(t) 偱偡丅
% psi_{n-2}(x) := x(1); psi_{n-1}(x) := x(2); psi_n(x) := 1 偱偡丅
%
% 'tp10': 1斣栚偺堷悢偵娭偡傞thin-plate僗僾儔僀儞偺曃旝暘
% psi_j(x) := phi(|x - c_j|^2) , j=1:n-1, 偙偙偱丄  
% phi(t) := (D_1 t)(log(t)+1)  偱偁傝丄 D_1 t 偼丄x(1) 偵偮偄偰偺
% t := t(x) := |x - c|^2 偺旝暘偱偡丅psi_n(x) := 1 偱偡丅
%
% 'tp01': 2斣栚偺堷悢偵娭偡傞thin-plate僗僾儔僀儞偺曃旝暘
% psi_j(x) := phi(|x - c_j|^2) , j=1:n-1, 偙偙偱丄
% phi(t) := (D_2 t)(log(t)+1)  偱偁傝丄 D_2 t 偼丄x(2) 偵偮偄偰偺
% t := t(x) := |x - c|^2 偺旝暘偱偡丅psi_n(x) := 1 偱偡丅
%
% 'tp': 弮悎側2曄悢thin-plate 僗僾儔僀儞 (僨僼僅儖僩) 
% psi_j(x) := phi(|x - c_j|^2), j=1:n, 偙偙偱丄phi(t) := t log(t)偱偡丅
%  
% ST = STMAK(CENTERS, COEFS, TYPE, INTERV) 偼丄st-宆偺婎杮嬫娫傪丄宍幃 
% {[a1,b1],...} 傪傕偮梌偊傜傟偨 INTERV 偵愝掕偟傑偡丅
% INTERV 偺僨僼僅儖僩偺抣偼丄偡傋偰偺拞怱傪娷傓嵟彫偺幉暯峴側儃僢僋僗
% 偱偡丅偡側傢偪丄[ai,bi] 偼 [min(CENTERS(i,:)),max(CENTERS(i,:))] 偱偡丅
% 偨偩偟丄偮偓偺椺奜偑偁傝傑偡丅1偮偩偗拞怱偑偁傞応崌丄婎杮嬫娫偼丄嵍壓偺
% 妏偲偟偰偦偺桞堦偺拞怱傪傕偮曈偺挿偝偑1偺儃僢僋僗偱偡丅 
%
% 嶲峫 STBRK, STCOL, FNBRK.


%   Copyright 1987-2004 C. de Boor and The MathWorks, Inc.