How to transfer value of a array to another array?

I have a problem to solve. How we can transfer value of one array to another array? For example,the sample code are as below:

a=zeros(2,5)
a(1,2)=2;a(1,4)=6;a(2,1)=8;a(2,3)=2
b(1,1)=1;b(1,2)=4;b(1,3)=1;b(2,1)=9;b(2,2)=1;b(2,3)=9

So, I want the value from array b will replace the 0 value in array a? How can I do it? I hope I can get help to do this.

Answer 1

[Fangjun Jiang]

Depending on the order you want,

a(a==0)=b(:)

or

b=b.';
a(a==0)=b(:)

[yue ishida]

Thank you very much! You're very helpful...