%* Euler single-step solution for decay series system of ODEs 
clear
 
lambda=[1 1 0];	% decay constants, incl. stable daughter
c0=[1 0 0];	% initial conditions on c
t0=0;			% initial time
tf=10;		% ending time for calculation
h=0.05;		% step size
 
 
t=[t0:h:tf]';           % independent variable
M=length(lambda);       % number of isotopes
N=length(t)-1;          % number of steps, N+1 = number of nodes
 
C=zeros(N+1, M);        % dependent variable
C(1,:)=c0;              % initial conditions
 
A=zeros(M,M);           % coefficients, -ve loss, +ve accumulation
A(1,1)=-lambda(1);       % primary parent, decay
for m=2:M
    A(m,m-1:m)=lambda(m-1:m);     % daughters
    A(m,m)=-1*A(m,m);    % decay
end