-@node Expressions, Data Input and Output, Language, Top
+@node Expressions
@chapter Mathematical Expressions
@cindex expressions, mathematical
@cindex mathematical expressions
PSPP supplies a few functions for date arithmetic:
-@deftypefn {Function} {} DATEDIFF (@var{date1}, @var{date2}, @var{unit})
+@deftypefn {Function} {} DATEDIFF (@var{date2}, @var{date1}, @var{unit})
Returns the span of time from @var{date1} to @var{date2} in terms of
@var{unit}, which must be a quoted string, one of @samp{years},
@samp{quarters}, @samp{months}, @samp{weeks}, @samp{days},