How to read data from xls file in loop?

I have one matrix("dummy") with some data in it. I want to sort that data and append it in a matrix which already has some data in it according to the relation satisfied by data. For that I want to run a loop which will read data and check the condition and then append it in the corresponding cell of file. I have written following code.

offset = ['A' 'B' 'C' 'D' 'E' 'F' 'G' 'H' 'I' 'J' 'K' 'L' 'M' 'N' 'O' 'P' 'Q' 'R' 'S' 'T' 'U' 'V' 'W' 'X' 'Y' 'Z'];
maxload = 0;        index_1 = 0;        index_2 = 0;        alpha = offset(1);     temp = dummy(1,1);     N_offset = 1;   
for i = 1:n(1,1)
   for j = 1:m(1,1)
      if(temp >= dummy(j,i) && maxload <= 100)
         temp = dummy(j,i);
         index_1 = i;
         index_2 = j;
      end
      maxload = maxload+delnode(4,i);   %add condition for delivery node also
   end
        for k = 1:m(1,1)
            columnB = xlsread('cluster.xls',1,'B%d',N_offset);
            N_offset = N_offset+1;
            if (index_2 == k)
                xlswrite('cluster.xls', delnode(:,index_1), 1, sprintf('%c1',(alpha)));
                alpha = offset(1+k);
            end
        end
end

But I get the following error.

Warning: Import mode string is invalid. XLSREAD resets mode to normal. 
> In xlsread at 170
  In VRP_ver2 at 73 
Error using xlsreadCOM (line 48)
Data range is invalid.

Error in xlsread (line 230)
        [numericData, textData, rawData, customOutput] = xlsreadCOM(file, sheet, range, Excel,
        customFun);

Error in VRP_ver2 (line 73)
            columnB = xlsread('cluster.xls',1,'B%d',N_offset);

Please help me in resolving this issue.

Thank You

Shashank Katiyar

Answer 1

[Jing]

Could you please format your code? it's hard to read!

The error is in xlsread line (line 73), for 'B%d', I think you should write ['B' num2str(N_offset)] in this line.

Answer 2

[Image Analyst]

You can't do this:

xlsread('cluster.xls',1,'B%d',N_offset);

You need to create the cell reference as a string, for example with sprintf():

cellReference = sprintf('B%d', N_offset);
columnB = xlsread('cluster.xls',1, cellReference);

I don't know how many times you're calling xlsread, but if it's more than 2 or 3 times, you really should consider using ActiveX. It will be A LOT faster since you will only launch and shut down Excel once instead of with every call to xlsread().