Finding columns that contain both integers and NaN

I have a matrix that contain Numerical values (float) and Categorical values (Int)

as

    A = 1   NaN   2.2   3.2  4
        NaN 7.9   5.1   NaN  5
        3    5.5  NaN   4.1  NaN
and I'd like to split it into matrices;

one contains the Int values and the other contains the float values as

     it = 1   4
          NaN 5
          3   NaN
and

    flt = NaN  2.2 3.2
          7.9  5.1 NaN
          5.5  NaN 4.1
i use the following code
    int_cols = all( round(A)==A, 1 ); %// logical indexing into integer columns
    it = A(:,int_cols);
    flt = A(:,~int_cols);

However, NaN isn't equal NaN so it appears in the flt matrix and it = [].

Are there any function that can help?

Answer 1

[David Young]

Yes, isnan(x) does what x == NaN would do if NaNs were equal to each other.

Answer 2

[the cyclist]

int_cols = all( round(A)==A | isnan(A), 1 ); %// logical indexing into integer columns
it = A(:,int_cols)
flt = A(:,~int_cols)

[the cyclist]

If the entries in A are have been computed in prior operations, you might also want to guard against floating point inaccuracies, such as the value "4" actually being 4.0000000000001. You could check for equality to within a specific tolerance, for example.