IFERROR returns a value you specify if a formula evaluates to an error; otherwise, returns the result of the formula.

A list of the supported functions is available at http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/functions

This function can be implemented as a custom function. Check the following resources for more details on how to achieve that:

- http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions
- https://github.com/telerik/xaml-sdk/tree/master/Spreadsheet/WPF/CustomFunctions

Implement support for cell references to columns and rows, e.g. $1:$2, A:D, etc.

Currently, CellSelection.SetValue throws ParseException, and CellSelection.SetValueAsFormula throws InvalidOperationException. 

At this point, the formatting can be applied only to the whole cell content.

Add APIs for creating and manipulating Chart objects.

Split allows you to split the window into different panes that each scroll separately. 

This feature is different than the horizontal/vertical split of freeze panes, which is supported.

Implement functionality to rotate the content of a cell.

Add support for conditional formatting of cells - allow applying of rules used during visualization of cells to automatically apply formatting depending on their values.

Add support for MID function. MID returns a specific number of characters from a text string, starting at the position you specify, based on the number of characters you specify.

MID(text, start_num, num_chars)

A list of the supported functions is available at http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/functions

This function can be implemented as a custom function. Check the following resources for more details on how to achieve that:

- http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions
- https://github.com/telerik/xaml-sdk/tree/master/Spreadsheet/WPF/CustomFunctions

Currently, the numbers in a CSV file are parsed as numbers, and the leading zeros are lost. In MS Excel, leading zeros could be preserved when the values are imported as text using the more sophisticated text import wizard (http://www.upenn.edu/computing/da/bo/webi/qna/iv_csvLeadingZeros.html ).

Workaround: The values could be extracted using a third-party (or custom) CSV parser, and inserted manually into the model, using CellSelection.SetValueAsText method (http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/working-with-cells/cell-value-types.html ).

Add support for creating Tables and applying tables styles (predefined ones or custom).

When defaultThemeVersion is missing from the file, some styles are not shown when the document is opened in MS Excel.

Add support for strikethrough font effect for cell formatting. Currently this is not supported by the model and is omitted on import.

Expose an easy way to create .xlsx documents from DataTable objects.

Add support for theme effects (format schemes). They are described in OOXML using the 'fmtScheme' element. Thing of providing predefined sets.

In MS Excel the UI for changing is located in Page Layout tab -> Themes -> Effects.

Add API for setting custom document properties (metadata). Such are visualized by the common editors, e.g. in MS Excel in the File menu.

Example properties that can be set through the document properties are:

- Title
- Subject
- Author
- Keywords
- Comments
- Last Author
- Creation Date
- Category
- Manager
- Company

If a worksheet spans more than one page, you can print row and column headings or labels (also called print titles) on every page to ensure that the data is properly labeled.

Provide an option to change the display mode of the Worksheet to right-to-left.

Add API to get the list of ranges to which a defined name refers.

Example:
List<CellRange> ranges = workbook.Names["definedName"].Ranges;
CellSelection selection = worksheet.Cells[ranges];

The cell range referred by the defined name could be accessed using code similar to the following one:
foreach (var name in workbook.Names)
{
    if (name.Name == givenName)
    {
        string[] v = name.RefersTo.Split("!".ToCharArray());

        foreach (Worksheet sheet in workbook.Sheets)
        {
            if (sheet.Name.ToUpper() == v[0].Replace("=", String.Empty).ToUpper())
            {
                string rangeName = v[1];
                string firstIndexName = rangeName.Split(":".ToCharArray())[0];

                int rowIndex;
                int columnIndex;
                bool isRowAbsolute;
                bool isColumnAbsolute;
                bool nameRefersToIndex = NameConverter.TryConvertCellNameToIndex(firstIndexName, out isRowAbsolute, out rowIndex, out isColumnAbsolute, out columnIndex);

                if (nameRefersToIndex)
                {
                    sheet.Cells[rowIndex, columnIndex].SetValue(givenValue);
                }
            }
        }
    }
}

When a chart is inserted in a document, generated by SpreadProcessing or WordsProcessing, the chart seems to lack any bars. The reason is that some theme information is missing, which effectively makes shapes take their default color, which is transparent. The same applies for shapes inserted in any Document Processing-generated OOXML documents - docx, xlsx.

Workaround: (applicable for Excel) Manually change the theme for the document in MS Excel:
- Choose Page Layout -> Themes -> Themes dropdown -> Office.