eval.jm causes R to evaluate the expression x as if it were entered at the keyboard.  If eval.jm is called by another function, it is evaluated within the environment of that function.  

x is a character string that corresponds to a function call.

Example:
eval.jm("ls()")
eval.jm("ls(pos=1)")

These two commands do not produce the same output.  The first shows that 'x' is the only object in the function environment, and this is different from the top environment in the search path.

'exists.jm' checks that each of a series of named objects
exists in the current workspace.
ARGUMENTS:
'x' = one or more names
'logical.only = FALSE' (default) - returns a dataframe with information
about the existence and location of each object in 'x'.  If TRUE,
the function returns only a logical vector indicating whether or not each
object named in 'x' exists on the search path.

Version 12/28/2006.

'input' = the R matrix or dataframe that is to be exported to SPSS.

'outfile' specifies the output file to which SPSS syntax and data will be written. 'outfile' should not have a file extension, i.e., it should have the form:  'outfile = c:\\mydata\\newdata' or 'outfile = c:/mydata/newdata'.  Either specification will cause SPSS syntax to be written to c:\mydata\newdata.sps and data in text format will be written to c:\mydata\newdata.txt.  

WARNING: If you write 'outfile = c:\mydata\newdata' as the 'outfile' argument of export.spss, R will not understand this path specification.  R expects to see '\\' or '/' where Windows expects to see '\'.

Digits = 8 is intended to control the number of digits to the right of the decimal place that are written to the data file, but at present this option is not working properly.  Need to debug this at some later time.

replace.file = FALSE means that no data or syntax files will be created if files by the same names already exist.  'replace.file = TRUE' means that 'export.spss' will overwrite any existing files that have the same names as the new syntax and data files.