Simple string to number help; how to convert this into a number?

I'm not sure how I would convert the string into a number for this part of my program;

   H1 = inputdlg('Number of rows');
%not sure how to get H1 to a number

   if H1 <=0
     H1 = inputdlg('Positive number of rows');
   else
     numRows = (H1);
   end

*Undefined function 'le' for input arguments of type 'cell'.*

trying to get H1 as a positive number but this error keeps showing up because it is a string

Answer 1

[Hikaru]

Assuming that H1 contains only one value, you could use

     n = H1{1} % to access that value in the cell
     if c <=0
      c = inputdlg('Positive number of rows');
     else
       numRows = (c); %note that numRows is stored as 'char'
     end

On a side note, is it really necessary to use inputdlg? You could store it as a double if you had use input instead.

H1 = input('Number of rows: ')