problem with xlsread:Bizarre results

Hi Sabbas I think its maybe impossible to debug this from here - all I can suggest is that the rows below are not actually empty but contain some character somewhere, putting a breakpoint in xlsread and stepping through should clarify this.

In general though, I think that you shouldn't be using xlsread at all (especially when you are running several of them in quick succession) as it instantiates an excel COM application object with each run. Use the Activex object directly and capture the data by invoking the VBA-type properties and methods of the excel COM Object, its much faster and you have more visibility on what is happening.

Below is a code snippet that you can adapt:

All the best,

Mark Whirdy

xlApp = actxserver('Excel.Application');
xlApp.Visible = 1;
xlWorkbook = xlApp.workbooks.Open(fullfile(xlFilePath,xlFileName),0,true);
xlSheets = xlWorkbook.Sheets;
xlSheetNamesArray = cell(xlSheets.Count,1); 
for i = 1:xlSheets.Count
    xlSheetNamesArray{i} = xlSheets.Item(i).Name; % sheet-order is not guaranteed so must build array
end

[~,idx] = ismember('Price',xlSheetNamesArray);
xlSheets.Item(idx).Activate
xlActiveSheet = xlWorkbook.ActiveSheet;
xlCurrRange = xlActiveSheet.Range('C4:C33');
priceVector = xlCurrRange.Value2;
priceVector = cell2mat(priceVector);

[~,idx] = ismember('Portfolios',xlSheetNamesArray);
xlSheets.Item(idx).Activate
xlActiveSheet = xlWorkbook.ActiveSheet;
xlCurrRange = xlActiveSheet.Range('B4:B22');
isinVector = xlCurrRange.Value2;
xlCurrRange = xlActiveSheet.Range('C3:G3');
ptfNumVector = cell2mat(xlCurrRange.Value2)';
xlCurrRange = xlActiveSheet.Range('C4:G22');
dataMatrix = xlCurrRange.Value2;

isnanMatrixMask = strcmp(dataMatrix,'ActiveX VT_ERROR: '); % handle missing data - assume as no position
dataMatrix(isnanMatrixMask) = {0};
dataMatrix = cell2mat(dataMatrix);

Hello,

I think the problem is with Excel.

I think you should have at a moment more than 245 lines, and you should have deleted them. You don't see these old lines in excel, but the application remains it. When you are using xlsread, you import these empty lines. You can see this with raw datas.

When you want import data from excel, 2 solutions:

• First, in excel you select all lines ( and after all columns ) after your data and you remove them (not only delete)

• !the other one, with raw data you can define lines and columns with no data or NaN data, and you delete them :

[ N, T, R ] = xlsread( ‘toto.xls’ );
Tmp = cellfun( @isnan, R, ‘UniformOuput’, true);
R( all( Tmp,1), : ) = [] ;
R( : , all( Tmp,2) ) = [] ;

Or something like this (I’m sorry but I don’t have Matlab on my Pc today) (it’s the same thing with “empty” )