Zakaria,

You simply need to cast the objects to the double data type:

MyTable.Rows[i]["Qx"] = (double)TableLx.Rows[i][1] + 1/(1.04)*(double)TableLx.Rows[i][1];

~~Bonnie



>Hello All,
>
>I have DataTable with some columns. The first column is filled with some double values. The other columns are empty, I want to fill those columns by performing some calculations on the content of the first column,like below:
>

>MyTable.Rows[i]["Qx"] = TableLx.Rows[i][1] + 1/(1.04)*TableLx.Rows[i][1];
>

>
>This is not possible because the Items are objects and you can't use the '+' operator. How to fill those columns then ?
>
>Thank you.
>
>Zakaria