Excel's Find function; Exceptions over values

this one helps. I have two excel files. , Use this:

=VLOOKUP(A2, '1st Excel'!A:B, 2, 0)

Any of those help You can use Math.NET.
The method you are looking for is MathNet.Numerics.Distribution.Normal.InverseCumulativeDistribution

wish helps you I have been googling this for a while and can´t seem to get it to work. I use Excel 2010 and want to count rows on a mix of AND and OR operators. , you can use

=SUM(COUNTIFS($A:$A,"string1",$B:$B,"string2",$C:$C,{"stringA","stringB","stringC"}))

=SUMPRODUCT(($A:$A="string1")*($B:$B="string2")*($C:$C={"stringA","stringB,"stringC"}))

I hope this helps . I am trying to access multiple excel files present in a folder,then find a particular sheet and then search a particular column(header is in the first row of the sheet). The column contains numeric values and I need to sum all the values for that column of the sheet and then paste the sum in a table creating a new excel.The output excel should contain the table having the sum of the values for that column of all the excels I accesse , Try this to sum the column values:

        decimal returnVal = 0;
        for (int i = 1; i < rowused; i++) //NB: off-by-one error here? Shouldn't it be from 1 to <= rows ?
        {
            cRng = (Excel.Range)xlWorkSheet.Cells[i, rngResult.Column];
            if (cRng != null)
            {
                decimal currentVal;
                if( decimal.TryParse(cRng.Value2.ToString(), out currentVal) )
                    returnVal += currentVal;
            }
        }
        return returnVal.ToString();

will be helpful for those in need Finally I find my mistake. This code was responsible for the strange behaviour. Apparently I cannot cast cell to other type and cast it back without destroying value.

int cellType = cell.getCellType();
cell.setCellType(Cell.CELL_TYPE_STRING);
String val = cell.getStringCellValue();
cell.setCellType(cellType);