Recursion Issue
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Hi again everyone, I am still trying to fix my recursion... If anyone could help me with these conditions that would be great I seem to keep on getting infinite recursions.
My codes are below:
Main:
close all
clear all
clc
theta = [-pi:pi/100:pi]';
plotValues = cos(theta);
lamda = [0:(2*pi)/100:(2*pi)]';
set1 = pnm(1,1,theta,1);
set2 = pnm(3,1,theta,1);
set3 = pnm(5,1,theta,1);
set4 = pnm(7,1,theta,1);
hold on
plot(plotValues,set1,'g');
plot(plotValues,set2,'r');
plot(plotValues,set3,'m');
plot(plotValues,set4,'b');
axis([-1 1 -4 4]);
legend('n=1; m=1','n=3; m=1', 'n=5; m=1', 'n=7; m=1')
hold off
%set1non = pnm(1,1,theta,0);
%set2non = pnm(3,1,theta,0);
%set3non = pnm(5,1,theta,0);
%set4non = pnm(7,1,theta,0);
%hold off
%hold on
%figure
%plot(plotValues,set1non,'g');
%plot(plotValues,set2non,'r');
%plot(plotValues,set3non,'m');
%plot(plotValues,set4non,'b');
%axis([-1 1 -4 4]);
%legend('n=1; m=1','n=3; m=1', 'n=5; m=1', 'n=7; m=1')
RnmZ = pnm(4,0,theta,1)*cos(0*lamda);
SnmZ = pnm(4,0,theta,1)*sin(0*lamda);
PNM:
function [ values ] = pnm( n,m,theta,norm )
%What to do...
if ((n ~= 0 && m ~= 0) || (n~=0 && m==0) || (n==0 && m~=0))
if (norm == 0 )
if (m >= 2)
pnmCurrentn = 2*(m-1)*((cos(theta)/sqrt(1-cos(theta)^2)))*pnm(n,m-1,theta,norm)-(n-m+2)*(n+m-1)*pnm(n,m-2,theta,norm);
values = pnmCurrentn;
elseif (norm == 0 && m == 0)
pn = -((n-1)/n)*pnm(n-2,0,theta,norm)+((2*n-1)/n)*(cos(theta))*pnm(n-1,0,theta,norm);
values = pn;
elseif ( n >= m+2)
pnmCurrentn = ((2*n-1)/(n-m)).*cos(theta).*pnm(n-1,m,theta,norm)-((n+m-1)/(n-m))*pnm(n-2,m,theta,norm);
values = pnmCurrentn;
elseif (n==1 && m==1)
values = sin(theta);
elseif ( n==2 && m ==1 )
values = 3.*sin(theta).*cos(theta);
end
elseif ( norm == 1)
if ( n == 1 && m == 1)
w11 = sqrt(3);
values = w11*sqrt((1-cos(theta).^2))*pnm(m-1,m-1,theta,norm);
elseif (( n==0 && m==0))
values = 1;
elseif ( n == m)
wmm = sqrt((2*m-1)/(2*m));
values = wmm.*(1-cos(theta).^2).^(1/2)*pnm(m-1,m-1,theta,norm);
elseif (n~=m || (n~=0 && m==0))
wnm = sqrt(((2*n+1)*(2*n-1))/((n+m)*(n-m)));
wnmB = sqrt(((2*(n-1)+1)*(2*(n-1)-1))/(((n-1)+m)*((n-1)-m)));
values = wnm*(cos(theta).*pnm(n-1,m,theta,norm)-inv(wnmB)*pnm(n-2,m,theta,norm));
end
end
elseif ((n == 0 && m == 0))
if (norm ~= 1)
values = 1;
elseif (norm == 1)
values = 1;
end
end
end
0 Comments
Accepted Answer
Oleg Komarov
on 11 Feb 2011
Andrew,
1) Deleting your old questions and posting incrementing new ones with highly related content instead of editing the original post, is not a nice way to recognize others effort.
2) On line 45:
pnm(n-2,m,theta,norm)
n is decreased by 2, but you supplied n = 3 with set2 = pnm(3,1,theta,1); , i.e. on the second recursion you'll call on line 45:
pnm(-1,1,theta,norm)
which will enter an endless recursion since you don't contemplate cases with negative values of n
Oleg
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