MATLAB read/write/control Excel

What XLSREAD and XLSWRITE do under the hood

On a Windows platform, MATLAB's XLSREAD and XLSWRITE open Excel as a COM automation server in the background to read/write data. Sometimes users want XLSREAD and XLSWRITE to do more, and would like their own custom XLSREAD or XLSWRITE functions (such as a custom XLSWRITE that puts data into multiple worksheets, and creates Excel charts at the same time).

Little new functionality is contained in this submission compared to what is already contained in Brett Shoelson's submission referenced below. Whereas Brett Shoelson's "Write2Excel.m" is a cleanly packaged solution, this is an open script intended to show what's going on, to empower users to create their own enhanced XLSREAD and XLSWRITE.