NaN selective removal from a matrix

I have a matrix like this: a=[NaN NaN NaN NaN;NaN NaN NaN NaN;2 3 NaN 4;9 4 NaN 4;3 9 NaN 3];

and i want to remove all the rows that contains only NaN's to: b=[2 3 NaN 4;9 4 NaN 4;3 9 NaN 3];

please help me,

Ziv.

Answer 1

[Jos (10584)]

tf1 = isnan(a)
tf2 = all(a,2) 
tf3 = ~tf2
b = a(tf3,:)
b2 = a(~all(isnan(a),2),:) % in one giant leap

[Ziv Kassner]

Great! worked perfectly!

Answer 2

[Andrei Bobrov]

b = a(any(a == a,2),:);