We have plenty of data buried in a lot of Excel files (.xls, .xlsx). The data comprises mainly statistics (first row comtains colum headers, first column contains row headers, rest of data are decimal numbers).
We want to provide this data in various file formats that better follow the open data best practices than Excel files. Excel has just 2 stars, we want more (see http://5stardata.info).
Since we live in an Linux world, we are looking for batch data conversion tools (libraries, scripts, tools, etc.) - PHP prefered, but this is no must - that convert these Excel files to
- CSV (decimal point, decimal comma)
- TSV (tab separated values)
- XML (schema file and data file)
- Maybe there are other open data formats, too.
...or at least some of them.
The Excel files are updated periodically (yearly, monthly,...), so the conversion process should be repeatable.
Some Excels have headers in multiple rows. How can we deal with that?