MATLAB: Finding negative numbers and showing where they are

load Saturated_Table % load tables
load SpecificHeat_Data

SAT = SaturatedTable; % storing the tables as variables
SH = SpecificHeatData;
 
NNeg = SaturatedTable(1:end , 2:end); % Selects 1st rown to the end, 2nd colum to the end of the table
%mustBeNonnegative(NNeg) %states that the values above must be nonnegative
if NNeg<0 
   disp(neg)
end 

Answer 1

[Walter Roberson]

[row, column] = find(NNeg < 0)

[Walter Roberson]

while true
    [row, column] = find(NNeg < 0, 1);
    if isempty(row); break; end
    newval = input( sprintf('Input non-negative for row %d column %d: ', row, columN);
    if isnumeric(newval) && isscalar(newval)
        NNeg(row, column) = newval;
    end
end