Example

> a = [ inf(),3,4,4,0]
 a =
 Infinity          3          4          4          0  
> all(a)
        0  
> b = [0,0,0]
 b =
        0          0          0  
> all(b)
        0  
> c = [ nan(),3,4,4,20]
 c =
      NaN          3          4          4         20  
> all(c)
        1  
> d = [a;b,7,3;c]
 d =
 Infinity          3          4          4          0  
        0          0          0          7          3  
      NaN          3          4          4         20  
> all(d)
        0          0          0          1          0  
> all(all(d))
        0