Error using vertcat Dimensions of arrays being concatenated are not consistent.

Dear all,

I implement this function:

function [SP_Simulation]=get_survivalprobability(a,b,w,dt,m,k)

for i=1:k

for j=1:m

hzrd(i,j)=exp(a(i)+b*w(i,j)) ;

end

end

h1=hzrd(1,:) ;

SP1=(sum(exp(h1*-dt)))/m ;

for i=1:k-1

h=(hzrd(i,:)+hzrd(i+1,:)).*-dt;

SP_others(i)=sum(exp(h),2)./m ;

SP_Simulation=[SP1 ; SP_others];

end

end

when I try to use it for the following main code:

k=5;

m=3000;

b=0.01 ;

SP=repmat(0.98,k,1) ;

w=rand(k,m);

fun=@(a) (get_survivalprobability(a,b,w,dt,m,k)-SP);

% find f(a)=0 such that equation (4.6) holds, given

% an initial guess a0

a0=ones(1,k);

[a] = fsolve(fun,a0);

% find hazard rates with the new parameters a

for i=1:k

for j=1:m

h(i,j)=exp(a(i)+b*w(i,j))

end

end

it shows me the following error: Error using vertcat Error using vertcat Dimensions of arrays being concatenated are not consistent.

Could someone please help me??

Thank you in advance

Regards,

Martina

Answer 1

[darova]

MATLAB doesn't know if SP_others is column or row vector. By default - row

SP_others(i)=sum(exp(h),2)./m ;

Then you are trying to concantenate

SP_Simulation=[SP1 ; SP_others];

Also i recommend you to pre-allocate memory for matrices

hzrd = zeros(k,m);
SP_others = zeros(k-1,1);        % COLUMN