Checking missing values in Tanagra
Up to the 1.4.41 version, Tanagra does not handle missing values because it seems interesting to force the students, which are the main users of Tanagra, to think about and to propose the most appropriate solution in relation with the characteristics of their dataset and the goal of their analysis. Thus, Tanagra simply truncates the file to import from the first obstacle. This treatment often disconcerts the users, especially since no error message was sent. They wondered why, whereas the conditions look right, the data were not properly loaded. From Tanagra 1.4.42 version, the importation of the text file format (tab separator), of the XLS file format (Excel 97-2003), and the data transfer using the add-in for Excel (up to Excel 2010 ) and LibreOffice 3.5/OpenOffice 3.3, have been modified. Tanagra reads all rows of the base. But it skips the incomplete rows and / or with inconsistencies (e.g. a column contains numeric value whereas this is a discrete attribute). And above all,...