This page provides raw data for determining the actual spreadsheet functions' definitions. In particular:
To run, it requirs a file named yearfrac_data_basis.txt in the same directory, with the expected values in "version 2" format. To create such a file, extract the yearfrac_data_basis_all.zip file. I normally create a symbolic link to the right file, e.g.,
ln -s yearfrac_data_basis1.txt yearfrac_data_basis.txtYou can also concatenate all the files from the "zip" file to create a single file with the whole test suite (it will take a while to run). At the end of the run it will print the number of correct and incorrect results; during its run, it will print ERROR with every error.
These are in "version 2" format; each line just has space-separated values for date1 (YYYY-MM-DD), date2 (YYYY-MM-DD), basis, and expected value. There are no line duplicates (though if the numbers appear different they duplicate, e.g., 0 vs. 0.00000000; this is harmless). Year 1900 is included; you probably want to ignore them.
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