how to write long field name in a shape file?

Hello everyone , I need to write new column in a shape file so I used setfield function

    SumOfLightColumn=strcat('Sum','20150201_20150228');
    SumOfLightColumn=char(SumOfLightColumn);%%convert it to character because it is a cell araay
    shapeToTable=struct2table(shape);

    n=num2cell(a); %%convert the a column vector from double to cell array so i can write in the table

    s=setfield(shapeToTable,SumOfLightColumn,n); %%n is a after convertion to a cell array 
  w = table2struct(s);
  shapefile1=fullfile(shapeFolder,baseShape); %%this the the path of the shape file
  shapewrite(w,shapefile1);

but the output of the field name is :Sum20150201 and when I run it for the second time it writes another column :Sum201502011 it doesn't take the whole name like this :Sum20150201_20150228

Does anyone know how to fix this? the attachment is a screenshot of the output shape file

Answer 1

[Rachana Reddy Mamilla]

Hello Reema, You cannot create fields whose size is greater than 11 characters using shapefile. Hence you face that issue. As you keep adding a column with the same field name, it keeps adding with a subscript. Ex. A file once saved as shape if you try to resave it, it gets saved as shape (1), shape(2) etc. It’s similar to this. You can refer to “When should I not use a shape file” in http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Geoprocessing_considerations_for_shapefile_output