Column Converter for Excel

Convert Excel column letters to numbers or vice versa, for processing data to/from XLSREAD/XLSWRITE.

B = XLSCOL(A) takes input A, and converts to corresponding output B. The input may be a number, a string, an array or matrix, an Excel range, a cell, or a combination of each within a cell, including nested cells and arrays.

The output maintains the shape of the input and attempts to "flatten" the cell to remove nesting.

Numbers and symbols within strings or Excel ranges are ignored.

Examples:
xlscol(256) % returns 'IV'
xlscol('IV') % returns 256
xlscol('A1:IV65536') % returns [1 256]

See more examples in help comments.

Notes:
CELLFUN and ARRAYFUN allow the program to recursively handle multiple inputs. An interesting side effect is that mixed input, nested cells, and matrix shapes can be processed.

Acknowledgment:
I adapted the modular math from Mike Sheppard's program ExcelCol, to properly handle the conversion from column number to strings. His program is at http://www.mathworks.com/matlabcentral/fileexchange/27182-excel-column-conversion