下面这个函数大家都不会陌生,计算zernike函数值的,并根据此可以还原出图像来, h-ii-c?R@0
我输入10阶的n、m,r,theta为38025*1向量,最后得到的z是29525*10阶的矩阵, BQPmo1B
这个,跟我们用zygo干涉仪直接拟合出的36项zernike系数,有何关系呢? D{B?2}X
那些系数是通过对29525*10阶的矩阵每列的值算出来的嘛? @l j|
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function z = zernfun(n,m,r,theta,nflag) 9k;,WU(K<
%ZERNFUN Zernike functions of order N and frequency M on the unit circle. 9DA|;|
% Z = ZERNFUN(N,M,R,THETA) returns the Zernike functions of order N Nksm&{=6S
% and angular frequency M, evaluated at positions (R,THETA) on the %.=}v7&<z
% unit circle. N is a vector of positive integers (including 0), and ~4~r
% M is a vector with the same number of elements as N. Each element D?_K5a&v,
% k of M must be a positive integer, with possible values M(k) = -N(k) Ps@']]4>W
% to +N(k) in steps of 2. R is a vector of numbers between 0 and 1, }lp37,
% and THETA is a vector of angles. R and THETA must have the same UnK7&Uo
% length. The output Z is a matrix with one column for every (N,M) {FFdMdxy-
% pair, and one row for every (R,THETA) pair. UPGUJ>2Z
% ]YI9
% Z = ZERNFUN(N,M,R,THETA,'norm') returns the normalized Zernike L/jaUt[,
% functions. The normalization factor sqrt((2-delta(m,0))*(n+1)/pi), ;B 8Q,.t>x
% with delta(m,0) the Kronecker delta, is chosen so that the integral >)M1X?HI5
% of (r * [Znm(r,theta)]^2) over the unit circle (from r=0 to r=1, E\/[hT
% and theta=0 to theta=2*pi) is unity. For the non-normalized 6Pl|FIJF
% polynomials, max(Znm(r=1,theta))=1 for all [n,m]. 3&})gU&a
% 5/n L[4Z
% The Zernike functions are an orthogonal basis on the unit circle. >Gpq{Ph[
% They are used in disciplines such as astronomy, optics, and I4@XOwl{P
% optometry to describe functions on a circular domain. -6DRX
% q~9-A+n
% The following table lists the first 15 Zernike functions. E:8*o7
% =OFhM7
% n m Zernike function Normalization b_ TI_
% -------------------------------------------------- EFC+7 L(j
% 0 0 1 1 mce qZv
% 1 1 r * cos(theta) 2 H14Q-2U1xa
% 1 -1 r * sin(theta) 2 op`9(=DJ]
% 2 -2 r^2 * cos(2*theta) sqrt(6) 7k*
% 2 0 (2*r^2 - 1) sqrt(3) x"q]~u<rB
% 2 2 r^2 * sin(2*theta) sqrt(6) rEWJ3*Hb
% 3 -3 r^3 * cos(3*theta) sqrt(8) lkT :e)w
% 3 -1 (3*r^3 - 2*r) * cos(theta) sqrt(8) ;&=jSgr8
% 3 1 (3*r^3 - 2*r) * sin(theta) sqrt(8) ~!Sd|e:4
% 3 3 r^3 * sin(3*theta) sqrt(8) CqEbQ>?
% 4 -4 r^4 * cos(4*theta) sqrt(10) 3]vVuQK .
% 4 -2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) |c0^7vrC
% 4 0 6*r^4 - 6*r^2 + 1 sqrt(5) Q*<KX2O
% 4 2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) s\mA3t
% 4 4 r^4 * sin(4*theta) sqrt(10) 3=n6NTL
% -------------------------------------------------- P+f}r^4}
% "mBM<rEn*
% Example 1: fCUx93,>z
% wY ItG"+6
% % Display the Zernike function Z(n=5,m=1) +&7V@
% x = -1:0.01:1; `l]Lvk8O
% [X,Y] = meshgrid(x,x); $!wU[/k
% [theta,r] = cart2pol(X,Y); ^|Z'}p|&
% idx = r<=1; uEb:uENk'(
% z = nan(size(X)); \r:*`Z*y
% z(idx) = zernfun(5,1,r(idx),theta(idx)); y%vAEQ2j=
% figure /(8"]f/
% pcolor(x,x,z), shading interp 3T.V*&
% axis square, colorbar `WH$rx!
% title('Zernike function Z_5^1(r,\theta)') 9BZ B1oX
% 1,=:an
% Example 2: H_f8/H
% !k%
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% % Display the first 10 Zernike functions m^XO77"
% x = -1:0.01:1; aR3jeB,=x
% [X,Y] = meshgrid(x,x); Kkq-x'gt^
% [theta,r] = cart2pol(X,Y); 3\RD%[}
% idx = r<=1; 7HW:;2dL
% z = nan(size(X)); (.=Y_g.
% n = [0 1 1 2 2 2 3 3 3 3]; Y}BP]#1
% m = [0 -1 1 -2 0 2 -3 -1 1 3]; +PE-j| D
% Nplot = [4 10 12 16 18 20 22 24 26 28]; fSd|6iFH
% y = zernfun(n,m,r(idx),theta(idx)); O$,
% figure('Units','normalized') F#|y,<}<
% for k = 1:10 &v0]{)PO
% z(idx) = y(:,k); ?J2A.x5`a
% subplot(4,7,Nplot(k)) @,oc%m
% pcolor(x,x,z), shading interp NpGi3>5
% set(gca,'XTick',[],'YTick',[]) `scW.Vem
% axis square sT1k]duT
% title(['Z_{' num2str(n(k)) '}^{' num2str(m(k)) '}']) KJJ:fG8'
% end 4J[zNB]
% 3M?O(oO
% See also ZERNPOL, ZERNFUN2. !EKt$8W
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% Paul Fricker 11/13/2006 4I&(>9 @z<
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% Check and prepare the inputs: O9N!SQs80
% ----------------------------- 'eBD/w5U
if ( ~any(size(n)==1) ) || ( ~any(size(m)==1) ) \y271}'
error('zernfun:NMvectors','N and M must be vectors.') ;B
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end LodP,\T
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if length(n)~=length(m) [@/p 8I
error('zernfun:NMlength','N and M must be the same length.') \YJQN3^46>
end JcYY*p
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n = n(:); `vzMuL;
m = m(:); J#H,QYnf(L
if any(mod(n-m,2)) 4_>;|2
error('zernfun:NMmultiplesof2', ... M*n94L=Sg&
'All N and M must differ by multiples of 2 (including 0).') OU` !c[O
end (D[~Z!
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if any(m>n) n}Eu^^d
error('zernfun:MlessthanN', ... tkm@&e=e%
'Each M must be less than or equal to its corresponding N.') whe%o
end
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if any( r>1 | r<0 ) VWt=9D;
error('zernfun:Rlessthan1','All R must be between 0 and 1.') 61QA<Wb
end :Nf(:D8
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if ( ~any(size(r)==1) ) || ( ~any(size(theta)==1) ) #s(ob `0|
error('zernfun:RTHvector','R and THETA must be vectors.') Ar~<l2,{r
end a5m[
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dm"x?[2:
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r = r(:); \kKd:C{
theta = theta(:); Qt\:A!'jw
length_r = length(r); D&K9!z"]
if length_r~=length(theta) Ok)f5")N %
error('zernfun:RTHlength', ... (qR;6l
'The number of R- and THETA-values must be equal.') GMZ6 dK
end 1Hhr6T^)
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% Check normalization: dm_Pz\*
% -------------------- 4W2.K0Ca
if nargin==5 && ischar(nflag) 9MJ:]F5+
isnorm = strcmpi(nflag,'norm'); *1-0s*T
if ~isnorm ^o>WCU =
error('zernfun:normalization','Unrecognized normalization flag.') L~h:>I+pG
end .
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else "+ {2!
isnorm = false; n(LO`{
end ;B2kot7
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% pHoxw|'Y
% Compute the Zernike Polynomials |;aZi?Ek[
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% w AdaP9h
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% Determine the required powers of r: ]X7_ji(l,
% ----------------------------------- QTF1~A\
m_abs = abs(m); ~ [/jk !G
rpowers = []; *'-C/
for j = 1:length(n) Z
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rpowers = [rpowers m_abs(j):2:n(j)]; ]fh(b)8_,
end bM_fuy55Op
rpowers = unique(rpowers); 5i{J0/'Xu)
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% Pre-compute the values of r raised to the required powers, YsiH=x
% and compile them in a matrix: ;InMgo,
% ----------------------------- A? jaS9 &)
if rpowers(1)==0 xi<}n#
rpowern = arrayfun(@(p)r.^p,rpowers(2:end),'UniformOutput',false); 6W]C`
rpowern = cat(2,rpowern{:}); d6m&nj
rpowern = [ones(length_r,1) rpowern]; 3AP=
else |V}tTx1
rpowern = arrayfun(@(p)r.^p,rpowers,'UniformOutput',false); .2rpQa/h
rpowern = cat(2,rpowern{:}); S+eu3nMq
end dF! B5(
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% Compute the values of the polynomials: 9P#kV@%(0c
% -------------------------------------- n^55G>"0|
y = zeros(length_r,length(n)); c":2<:D&
for j = 1:length(n) Kn?h
s = 0:(n(j)-m_abs(j))/2; }43qpJe8U
pows = n(j):-2:m_abs(j); )VG>6x
for k = length(s):-1:1
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p = (1-2*mod(s(k),2))* ...
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prod(2:(n(j)-s(k)))/ ... 48;b
prod(2:s(k))/ ...
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prod(2:((n(j)-m_abs(j))/2-s(k)))/ ... DtS7)/<T
prod(2:((n(j)+m_abs(j))/2-s(k))); 4}0YLwgJ
idx = (pows(k)==rpowers); n#?y;Y\
y(:,j) = y(:,j) + p*rpowern(:,idx); >*^SQ{9
end nemC-4}
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if isnorm J5f}-W@
y(:,j) = y(:,j)*sqrt((1+(m(j)~=0))*(n(j)+1)/pi); ?%Q=l;W.
end .k
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end Ya<V@qd
% END: Compute the Zernike Polynomials a>Aq/=
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% eAQ-r\h'2
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% Compute the Zernike functions: :UKc:JVNM
% ------------------------------ hv|-`}#0
idx_pos = m>0; @L607[!?
idx_neg = m<0; mZ?QtyljT
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VS~+W=5}
z = y; LH@Kn?R6
if any(idx_pos) }KftVnD?
z(:,idx_pos) = y(:,idx_pos).*sin(theta*m(idx_pos)'); BoARM{m
end m("KLp8
if any(idx_neg) <
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z(:,idx_neg) = y(:,idx_neg).*cos(theta*m(idx_neg)'); u<Ch]m+
end "r@G V5ED
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% EOF zernfun c|iTRco