extract column name of table with Nan column

How can i return the label name of column with values all Nan

sample1=[1 2 3]';%Sample data
sample2=[4 5 6]';%Sample data
sample3=[7 8 9]';%Sample data
sample4=nan(3,1);%Sample data
patients = table(sample4,sample2,sample3)

sample4    sample2    sample3
    _______    _______    _______

    NaN        4          7      
    NaN        5          8      
    NaN        Nan        9      

output should be 'sample4' as cell array

    NanLabels={'sample4'}

Answer 1

[madhan ravi]

patients.Properties.VariableNames(all(isnan(patients{:,:})))

[joms]

Thank you very much madhan ravi! This is exactly im looking for.

Answer 2

[Peter Perkins]

Using {:,:} to convert the entire table to a homogeneous array is perhaps one way to do this, but scales badly very quickly as the table gets big.

allMissing = all(ismissing(patients),1)

gives you a logical vector of variables in the table all of whose values are missing (whether or not they are numeric). Use that as a subscript into patients.Properties.VariableNames.